3-Arylbenzofuranones with electron-withdrawing substituents as stabilizers

ABSTRACT

The invention describes novel compounds of the formula (I) wherein the general symbols are as defined in claim (1) and R 1  is an aromatic radical with electron withdrawing substituents, as stabilizers for protecting organic materials, in particular polymers and lubricants, against oxidative, thermal or light-induced degradation and as scavengers for oxidized developer in color photographic material.

[0001] The present invention relates to novel 3-arylbenzofuranones, to compositions comprising an organic material, preferably a polymer or a lubricant, and to the novel stabilizers, as well as to the use thereof for stabilizing organic materials against oxidative, thermal or light-induced degradation and to the use of the novel stabilizers as scavengers for the oxidized developer (also termed hereafter Dox scavengers) in color photographic material.

[0002] It is well known that one of the problems associated with color photography is the diffusion of the oxidized color developer away from the light sensitive silver halide emulsion layer in which it is formed into another silver halide emulsion layer, which can result in the formation of unwanted dyes at undesired places. For instance, while being generated in the green sensitive layer and forming a magenta dye through a coupling reaction with the incorporated magenta coupler, the oxidized developer can also diffuse to the red sensitive layer thereby producing unwanted cyan dye or to the blue sensitive layer thereby producing unwanted yellow dye. This kind of color formation in the wrong layers will damage the color balance of the photographic image and thus results in poor color reproduction. One way of circumventing this problem is to incorporate oxidized developer scavengers in interlayers between the light sensitive silver halide emulsion layers. These scavengers should have additional properties such as low tendency to migrate, good stability towards aerial oxidation and high solubility in photographic oils.

[0003] Hydroquinone derivatives which are useful as scavengers for oxidized developers are for example described in U.S. Pat. No. 4,345,016.

[0004] The use of some 3-phenyl-3H-benzofuran-2-ones as stabilizers for organic polymers is disclosed, inter alia in WO-A-80/01566 and U.S. Pat. No. 5,516,920.

[0005] It has now been found that a selected group of 3-arylbenzofuran-2-ones with electron-withdrawing substituents is particularly suitable for use as stabilizers for organic materials that are susceptible to oxidative, thermal or light-induced degradation. These new compounds are also particularly suitable as Dox scavengers in color photographic material.

[0006] Accordingly, the invention relates to compounds of the formula I

[0007] wherein, when n is 1,

[0008] R₁ is a radical of the formula II, III or IV

[0009] and

[0010] when n is 2,

[0011] R₂, R₃, R₄ and R₅ are each independently of one another hydrogen, chloro, hydroxyl, C₁-C₂₅-alkyl, C₇-C₉phenylalkyl, unsubstituted or C₁-C₄alkyl-substituted phenyl; unsubstituted or C₁-C₄alkyl-substituted C₅-C₈cycloalkyl; C₁-C₁₈alkoxy, C₁-C₁₈alkylthio, C₁-C₄alkylamino, di-(C₁-C₄alkyl)amino, C₁-C₂₅alkanoyloxy, C₁-C₂₅alkanoylamino, C₃-C₂₅alkenoyloxy, C₃-C₂₅alkanoyloxy which is interrupted by oxygen, sulfur or

[0012] ; C₆-C₉cycloalkylcarbonyloxy, benzoyloxy or C₁-C₁₂alkyl-substituted benzoyloxy; or each pair of substituents R₂ and R₃ or R₃ and R₄ or R₄ and R₅ together with the linking carbon atoms, forms a benzene ring; or R₄ is additionally —(CH₂)_(p)—COR₁₉ or —(CH₂)_(q)OH, or when R₃, R₅ and R₆ are hydrogen, R₄ is additionally a radical of the formula V

[0013] wherein R₁ is as defined above for n=1,

[0014] R₆ is hydrogen or a radical of the formula VI

[0015] in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1,

[0016] R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ and R₁₅ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₁₂alkyl; —CN,

[0017] —SOR₂₆, —SO₂R₂₆ or SO₃R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ or R₁₅ is not hydrogen,

[0018] R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene which are substituted by fluoro, fluoro-substituted C₁-C₁₂alkyl, —CN,

[0019] —SOR₂₆, —SO₂R₂₆ or SO₃R₂₆,

[0020] R₁₈ is hydrogen or C₁-C₈alkyl,

[0021] R₁₉ is hydroxyl, $\left\lbrack {{—O}^{-}\frac{1}{r}M^{r +}} \right\rbrack,$

[0022] , C₁-C₁₈alkoxy or

[0023] R₂₀ and R₂₁ are each independently of one another hydrogen, CF₃, C₁-C₁₂alkyl or phenyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a C₅-C₈cycloalkylidene ring which is unsubstituted or substituted by 1 to 3 C₁-C₄alkyl groups;

[0024] R₂₂ is hydrogen, hydroxyl, $\left\lbrack {{—O}^{-}\frac{1}{r}M^{r +}} \right\rbrack,$

[0025] , C₁-C₂₅alkyl, C₇-C₉phenylalkyl, unsubstituted or C₁-C₄alkyl-substituted phenyl; unsubstituted or C₁-C₄alkyl-substituted C₅-C₈cycloalkyl; or C₃-C₂₅alkyl which is interrupted by oxygen, sulfur or

[0026] R₂₃ is C₁-C₂₅alkyl, C₇-C₉phenylalkyl, unsubstituted or C₁-C₄alkyl-substituted phenyl; unsubstituted or C₁-C₄alkyl-substituted C₅-C₈cycloalkyl; or C₃-C₂₅alkyl which is interrupted by oxygen, sulfur or

[0027] R₂₄ and R₂₅ are each independently of one another hydrogen, C₁-C₂₅alkyl, hydroxyl-substituted C₂-C₂₄alkyl; C₃-C₂₅alkyl which is interrupted by oxygen, sulfur or

[0028] C₇-C₉-phenylalkyl which is unsubstituted or is substituted on the phenyl ring by C₁-C₄alkyl; or C₃-C₂₄alkenyl; or R₂₄ and R₂₅, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring which is unsubstituted or is substituted by C₁-C₄alkyl or is interrupted by oxygen, sulfur or

[0029] R₂₆ is hydrogen or C₁-C₂₅alkyl,

[0030] R₂₇ and R₂₈ are each independently of one another hydrogen, C₁-C₂₅alkyl, hydroxyl-substituted C₂-C₂₄alkyl; C₃-C₂₅alkyl which is interrupted by oxygen, sulfur or

[0031] C₇-C₉-phenylalkyl which is unsubstituted or is substituted on the phenyl ring by C₁-C₄alkyl; or C₃-C₂₄alkenyl; or R₂₇ and R₂₈, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring which is unsubstituted or is substituted by C₁-C₄alkyl or is interrupted by oxygen, sulfur or

[0032] R₂₉ and R₃₀ are each independently of one another hydrogen, C₁-C₁₈alkyl or C₇-C₉phenylalkyl, or R₂₉ and R₃₀ together with the nitrogen atom to which they are attached form a 5-, 6- or 7-membered heterocyclic ring which is unsubstituted or is substituted by C₁-C₄alkyl or is interrupted by oxygen, sulfur or

[0033] X₁ is a direct bond, C₁-C₁₈alkylene, C₂-C,₈alkylene which is interrupted by oxygen, sulfur or

[0034] C₂-C₁₈alkenylene, C₂-C₂₀alkylidene, C₇-C₂₀phenylalkylidene, C₅-C₈cycloalkylene, C₇-C₈bicycloalkylene, unsubstituted or C₁-C₄alkyl-substituted phenylene,

[0035] —O—X₃—O—,

[0036] X₂ is C₂-C₁₈alkylene, C₄-C₁₈alkylene which is interrupted by oxygen, sulfur or

[0037] C₂-C₁₈alkenylene, C₅-C₈cycloalkylene, C₇-C₈bicycloalkylene, unsubstituted or C₁-C₄alkyl-substituted phenylene,

[0038] X₃ is C₂-C₁₈alkylene, C₄-C₁₈alkylene which is interrupted by oxygen, sulfur or

[0039] C₂-C₁₈alkenylene, C₅-C₈cycloalkylene, C₇-C₈bicycloalkylene, unsubstituted or C₁-C₄alkyl-substituted phenylene,

[0040] M is a metal cation of valency r,

[0041] n is 1 or 2,

[0042] p is 0, 1 or 2,

[0043] q is 1, 2, 3, 4, 5 or 6, and

[0044] r is 1, 2 or 3.

[0045] Alkanoyloxy having up to 25 carbon atoms is a branched or unbranched radical, for example formyloxy, acetoxy, propionyloxy, butanoyloxy, pentanoyloxy, hexanoyloxy, heptanoyloxy, octanoyloxy, nonanoyloxy, decanoyloxy, undecanoyloxy, dodecanoyloxy, tridecanoyloxy, tetradecanoyloxy, pentadecanoyloxy, hexadecanoyloxy, heptadecanoyloxy, octadecanoyloxy, icosanoyloxy or docosanoyloxy. Preference is given to alkanoyloxy having from 2 to 18, especially from 2 to 12, e.g. from 2 to 6, carbon atoms. Special preference is given to acetoxy.

[0046] C₃-C₂₅Alkanoyloxy interrupted by oxygen, sulfur or by

[0047] is, for example, CH₃—O—CH₂COO—, CH₃—S—CH₂COO—, CH₃—N(CH₃)—CH₂COO—, CH₃—O—CH₂CH₂—O—CH₂COO—, CH₃—(O—CH₂CH₂—)₂O—CH₂COO—, CH₃—(O—CH₂CH₂—)₃O—CH₂COO— or CH₃—(O—CH₂CH₂—)₄O—CH₂COO—.

[0048] C₆-C₉Cycloalkylcarbonyloxy is, for example, cyclopentylcarbonyloxy, cyclohexylcarbonyloxy, cycloheptylcarbonyloxy or cyclooctylcarbonyloxy. Preference is given to cyclohexylcarbonyloxy.

[0049] C₃-C₂₅Alkenoyloxy interrupted by oxygen, sulfur or by

[0050] is, for example, CH₃OCH₂CH₂CH═CHCOO— or CH₃OCH₂CH₂OCH═CHCOO—.

[0051] C₁-C₁₂Alkyl-substituted benzoyloxy, which carries preferably from 1 to 3, especially 1 or 2, alkyl groups, is, for example, o-, m- or p-methylbenzoyloxy, 2,3-dimethylbenzoyloxy, 2,4-dimethylbenzoyloxy, 2,5-dimethylbenzoyloxy, 2,6-dimethylbenzoyloxy, 3,4-dimethylbenzoyloxy, 3,5-dimethylbenzoyloxy, 2-methyl-6-ethylbenzoyloxy, 4-tert-butylbenzoyloxy, 2-ethylbenzoyloxy, 2,4,6-trimethylbenzoyloxy, 2,6-dimethyl-4-tert-butylbenzoyloxy or 3,5-di-tert-butylbenzoyloxy. Preferred substituents are C₁-C₈alkyl, especially C₁-C₄alkyl.

[0052] Alkyl having up to 25 carbon atoms is a branched or unbranched radical, for example methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, 2-ethylbutyl, n-pentyl, isopentyl, 1-methylpentyl, 1,3-dimethylbutyl, n-hexyl, 1-methylhexyl, n-heptyl, isoheptyl, 1,1,3,3-tetramethylbutyl, 1-methylheptyl, 3-methylheptyl, n-octyl, 2-ethylhexyl, 1,1,3-trimethylhexyl, 1,1,3,3-tetramethylpentyl, nonyl, decyl, undecyl, 1-methylundecyl, dodecyl, 1,1,3,3,5,5-hexamethylhexyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, icosyl or docosyl. One of the preferred definitions for R₂ and R₄ is, for example, C₁-C₁₈alkyl. An especially preferred definition for R₄ is C₁-C₄alkyl.

[0053] C₃-C₂₅Alkyl interrupted by oxygen, sulfur or by

[0054] is, for example, CH₃—O—CH₂CH₂—, CH₃—S—CH₂CH₂—, CH₃—N(CH₃)—CH₂CH₂—, CH₃—O—CH₂CH₂—O—CH₂CH₂—, CH₃—(O—CH₂CH₂—)₂O—CH₂CH₂—, CH₃—(O—CH₂CH₂—)₃O—CH₂CH₂— or CH₃—(O—CH₂CH₂—)₄O—CH₂CH₂—.

[0055] Fluoro-substituted C₁-C₁₂alkyl is a branched or unbranched radical, for example fluoromethyl, difluoromethyl, trifluoromethyl or pentafluoroethyl. Trifluoromethyl is preferred.

[0056] C₇-C₉Phenylalkyl is, for example, benzyl, α-methylbenzyl, α,α-dimethylbenzyl or 2-phenylethyl. Preference is given to benzyl and α,α-dimethylbenzyl.

[0057] C₇-C₉Phenylalkyl unsubstituted or substituted on the phenyl radical by from 1 to 3 C₁-C₄alkyl groups is, for example, benzyl, α-methylbenzyl, α,α-dimethylbenzyl, 2-phenylethyl, 2-methylbenzyl, 3-methylbenzyl, 4-methylbenzyl, 2,4-dimethylbenzyl, 2,6-dimethylbenzyl or 4-tertbutylbenzyl. Preference is given to benzyl.

[0058] C₁-C₄Alkyl-substituted phenyl, which contains preferably from 1 to 3, especially 1 or 2, alkyl groups, is, for example, o-, m- or p-methylphenyl, 2,3-dimethylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6-dimethylphenyl, 3,4-dimethylphenyl, 3,5-dimethylphenyl, 2-methyl-6-ethylphenyl, 4-tert-butylphenyl, 2-ethylphenyl or 2,6-diethylphenyl.

[0059] Unsubstituted or C₁-C₄alkyl-substituted C₅-C₈cycloalkyl is, for example, cyclopentyl, methylcyclopentyl, dimethylcyclopentyl, cyclohexyl, methylcyclohexyl, dimethylcyclohexyl, trimethylcyclohexyl, tert-butylcyclohexyl, cycloheptyl or cyclooctyl. Preference is given to cyclohexyl and tert-butylcyclohexyl.

[0060] Alkoxy having up to 18 carbon atoms is a branched or unbranched radical, for example methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, isobutoxy, pentyloxy, isopentyloxy, hexyloxy, heptyloxy, octyloxy, decyloxy, tetradecyloxy, hexadecyloxy or octadecyloxy. Preference is given to alkoxy having from 1 to 12, especially from 1 to 8, e.g. from 1 to 6, carbon atoms.

[0061] Alkylthio having up to 18 carbon atoms is a branched or unbranched radical, for example methylthio, ethylthio, propylthio, isopropylthio, n-butylthio, isobutylthio, pentylthio, isopentylthio, hexylthio, heptylthio, octylthio, decylthio, tetradecylthio, hexadecylthio or octadecylthio. Preference is given to alkylthio having from 1 to 12, especially from 1 to 8, e.g. from 1 to 6, carbon atoms.

[0062] Alkylamino having up to 4 carbon atoms is a branched or unbranched radical, for example methylamino, ethylamino, propylamino, isopropylamino, n-butylamino, isobutylamino or tert-butylamino.

[0063] Di(C₁-C₄alkyl)amino means also that the two radicals are each independently of the other branched or unbranched, for example, dimethylamino, methylethylamino, diethylamino, methyl-n-propylamino, methylisopropylamino, methyl-n-butylamino, methylisobutylamino, ethylisopropylamino, ethyl-n-butylamino, ethylisobutylamino, ethyl-tert-butylamino, diethylamino, diisopropylamino, isopropyl-n-butylamino, isopropylisobutylamino, di-n-butylamino or di-isobutylamino.

[0064] Alkanoylamino having up to 25 carbon atoms is a branched or unbranched radical, for example formylamino, acetylamino, propionylamino, butanoylamino, pentanoylamino, hexanoylamino, heptanoylamino, octanoylamino, nonanoylamino, decanoylamino, undecanoylamino, dodecanoylamino, tridecanoylamino, tetradecanoylamino, pentadecanoylamino, hexadecanoylamino, heptadecanoylamino, octadecanoylamino, icosanoylamino or docosanoylamino. Preference is given to alkanoylamino having from 2 to 18, especially from 2 to 12, e.g. from 2 to 6, carbon atoms.

[0065] C₁-C₁₈Alkylene is a branched or unbranched radical, for example methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, decamethylene, dodecamethylene or octadecamethylene. A preferred definition for X₁ is C₁-C₁₂alkylene, especially C₁-C₈alkylene, for example C₁-C₈alkylene. A preferred definition for X₂ is C₂-C₁₈alkylene, especially C₂-C₈alkylene. A preferred definition for X₃ is C₂-C₁₈alkylene, especially C₂-C₁₂alkylene, for example C₄-C₁₂alkylene.

[0066] C₂-C₁₈Alkylene interrupted by oxygen, sulfur or by

[0067] is, for example, —CH₂—O—CH₂—, —CH₂—S—CH₂—, —CH₂—N(CH₃)—CH₂—, —CH₂—O—CH₂CH₂—, —CH₂CH₂—O—CH₂CH₂—, —CH₂CH₂—O—CH₂CH₂—O—CH₂CH₂—, —CH₂CH₂—(O—CH₂CH₂—)₂O—CH₂CH₂—, —CH₂CH₂—(O—CH₂CH₂—)₃O—CH₂CH₂—, —CH₂CH₂—(O—CH₂CH₂—)₄O—CH₂CH₂— or —CH₂CH₂—S—CH₂CH₂—.

[0068] Alkylidene having from 2 to 20 carbon atoms is, for example, ethylidene, propylidene, butylidene, pentylidene, 4-methylpentylidene, heptylidene, nonylidene, tridecylidene, nonadecylidene, 1-methylethylidene, 1-ethylpropylidene or 1-ethylpentylidene. Preference is given to C₂-C₈alkylidene.

[0069] Phenylalkylidene having from 7 to 20 carbon atoms is, for example, benzylidene, 2-phenylethylidene or 1 -phenyl-2-hexylidene. Preference is given to C₇-C₉phenylalkylidene.

[0070] C₅-C₈Cycloalkylene is a saturated hydrocarbon group having two free valences and at least one ring unit and is, for example, cyclopentylene, cyclohexylene, cycloheptylene or cyclooctylene. Preference is given to cyclohexylene.

[0071] C₇-C₈Bicycloalkylene is, for example, bicycloheptylene or bicyclooctylene.

[0072] Phenylene or naphthylene each unsubstituted or substituted by C₁-C₄alkyl, fluoro, trifluoromethyl or —CN is, for example, 1,2-, 1,3- or 1,4-phenylene; 1,2-, 1,3-, 1,4-, 1,6-, 1,7-, 2,6- or 2,7-naphthylene; 1,4-(2-trifluormethyl)phenylene, 1,4-(2-trifluormethyl)naphthylene or 1,4-(2-cyano)phenylene.

[0073] A C₅-C₈cycloalkylidene ring substituted by C₁-C₄alkyl, which contains preferably from 1 to 3, especially 1 or 2, branched or unbranched alkyl group radicals, is, for example, cyclopentylidene, methylcyclopentylidene, dimethylcyclopentylidene, cyclohexylidene, methylcyclohexylidene, dimethylcyclohexylidene, trimethylcyclohexylidene, tert-butylcyclohexylidene, cycloheptylidene or cyclooctylidene. Preference is given to cyclohexylidene and tert-butylcyclohexylidene.

[0074] A mono-, di- or tri-valent metal cation is preferably an alkali metal cation, alkaline earth metal cation or aluminium cation, for example Na⁺, K⁺, Mg⁺⁺, Ca⁺⁺ or Al⁺⁺⁺.

[0075] Hydroxyl-substituted C₂-C₂₄alkyl is a branched or unbranched radical which contains preferably 1 to 3, in particular 1 or 2, hydroxyl groups, such as, for example, hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 4-hydroxybutyl, 3-hydroxybutyl, 2-hydroxybutyl, 5-hydroxypentyl, 4-hydroxypentyl, 3-hydroxypentyl, 2-hydroxypentyl, 6-hydroxyhexyl, 5-hydroxyhexyl, 4-hydroxyhexyl, 3-hydroxyhexyl, 2-hydroxyhexyl, 7-hydroxyheptyl, 6-hydroxyheptyl, 5-hydroxyheptyl, 4-hydroxyheptyl, 3-hydroxyheptyl, 2-hydroxyheptyl, 8-hydroxyoctyl, 7-hydroxyoctyl, 6-hydroxyoctyl, 5-hydroxyoctyl, 4-hydroxyoctyl, 3-hydroxyoctyl, 2-hydroxyoctyl, 9-hydroxynonyl, 10-hydroxydecyl, 11-hydroxyundecyl, 12-hydroxydodecyl, 13-hydroxytridecyl, 14-hydroxytetradecyl, 15-hydroxypentadecyl, 16-hydroxyhexadecyl, 17-hydroxyheptadecyl, 18-hydroxyoctadecyl, 20-hydroxyeicosyl or 22-hydroxydocosyl. A preferred definition of R₂₄, R₂₅, R₂₇ and R₂₈ is hydroxyl-substituted C₄-C₁₂alkyl, especially hydroxyl-substituted C₅-C₁₂alkyl, for example hydroxyl-substituted C₅-C₁₁alkyl. One of the preferred definitions of R₂₄, R₂₅ R₂₇ and R₂₈ is hydroxyl-substituted C₂-C₂₀alkyl, especially hydroxyl-substituted C₂-C₁₈alkyl, for example hydroxyl-substituted C₂-C₁₄alkyl. A particularly preferred definition of R₂₄, R₂₅ R₂₇ and R₂₈ is hydroxyl-substituted C₂-C₁₂alkyl, especially hydroxyl-substituted C₂-C₈alkyl, for example hydroxyl-substituted C₂-C₄alkyl, such as 2-hydroxyethyl, for example.

[0076] Alkenyl having 3 to 24 carbon atoms is a branched or unbranched radical such as, for example, propenyl, 2-butenyl, 3-butenyl, isobutenyl, n-2,4-pentadienyl, 3-methyl-2-butenyl, n-2-octenyl, n-2-dodecenyl, iso-dodecenyl, oleyl, n-2-octadecenyl or n-4-octadecenyl. Preference is given to alkenyl having 3 to 18, especially 3 to 12, for example 3 to 6, especially 3 to 4 carbon atoms.

[0077] Where R₂₄ and R₂₅ or R₂₇ and R₂₈, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring which is unsubstituted or is substituted by C₁-C₄alkyl or is interrupted by oxygen, sulfur or

[0078] this denotes, for example, the following radicals:

[0079] R₂₄ and R₂₅ or R₂₇ and R₂₈ preferably form, with the nitrogen atom to which they are attached, a 6-membered heterocyclic ring interrupted by oxygen, such as, for example,

[0080] Where R₂₉ and R₃₀, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring which is unsubstituted or is substituted by C₁-C₄alkyl or is interrupted by oxygen, sulfur or

[0081] this denotes, for example, the following radicals:

[0082] C₂-C₁₈Alkenylene is, for example, vinylene, methylvinylene, octenylethylene or dodecenylethylene. C₂-C₈Alkenylene is preferred.

[0083] Preferred compounds of the formula I are those wherein,

[0084] when n is 1,

[0085] R₁ is a radical of the formula II, III or IV

[0086] and

[0087] when n is 2,

[0088] R₂, R₃, R₄ and R₅ are each independently of one another hydrogen, chloro, hydroxyl, C₁-C₁₈-alkyl, C₇-C₉phenylalkyl, phenyl, C₅-C₈cycloalkyl, C₁-C₁₈alkoxy, C₁-C₁₈alkylthio, C₁-C₁₈alkanoyloxy, C₁-C₁₈alkanoylamino, C₃-C₁₈alkenoyloxy, C₃-C₁₈alkanoyloxy which is interrupted by oxygen or sulfur; C₆-C₉cycloalkylcarbonyloxy, benzoyloxy or C₁-C₄alkyl-substituted benzoyloxy; or each pair of substituents R₂ and R₃ or R₃ and R₄ or R₄ and R₅ together with the linking carbon atoms, forms a benzene ring; or R₄ is additionally —(CH₂)_(p)—COR₁₉ or —(CH₂)_(q)OH, or when R₃, R₅ and R₆ are hydrogen, R₄ is additionally a radical of the formula V

[0089] wherein R₁ is as defined above for n=1,

[0090] R₆ is hydrogen or a radical of the formula VI

[0091] in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1,

[0092] R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ and R₁₅ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₈alkyl; —CN,

[0093] —SOR₂₆, —SO₂R₂₆ or SO₃R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ or R₁₅ is not hydrogen,

[0094] R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene which are substituted by fluoro, trifluoromethyl, —CN,

[0095] —SOR₂₆, —SO₂R₂₆ or SO₃R₂₆,

[0096] R₁₈ is hydrogen or C₁-C₄alkyl,

[0097] R₁₉ is hydroxyl, $\left\lbrack {{—O}^{-}\frac{1}{r}M^{r +}} \right\rbrack,$

[0098] C₁-C₁₈alkoxy or

[0099] R₂₀ and R₂₁ are each independently of one another hydrogen, CF₃, C₁-C₈alkyl or phenyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a C₅-C₈cycloalkylidene ring;

[0100] R₂₂ is hydrogen, hydroxyl, $\left\lbrack {{—O}^{-}\frac{1}{r}M^{r +}} \right\rbrack,$

[0101] C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, C₅-C₈-cycloalkyl; or C₃-C₂₅alkyl which is interrupted by oxygen or sulfur,

[0102] R₂₃ is C₁-C₂alkyl, C₇-C₉phenylalkyl, phenyl, C₅-C₈cycloalkyl or C₃-C₂₅alkyl which is interrupted by oxygen or sulfur,

[0103] R₂₄ and R₂₅ are each independently of one another hydrogen, C₁-C₁₈alkyl, hydroxyl-substituted C₂-C₁₈alkyl; C₃-C₁₈alkyl which is interrupted by oxygen, sulfur or

[0104] C₇-C₉-phenylalkyl, or C₃-C₁₈alkenyl; or R₂₄ and R₂₅, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring,

[0105] R₂₆ is hydrogen or C₁-C₁₈alkyl,

[0106] R₂₇ and R₂₈ are each independently of one another hydrogen, C₁-C₁₈alkyl, hydroxyl-substituted C₂-C₁₈alkyl; C₃-C₁₈alkyl which is interrupted by oxygen, sulfur or

[0107] C₇-C₉-phenylalkyl, or C₃-C₁₈alkenyl; or R₂₇ and R₂₈, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring,

[0108] R₂₉ and R₃₀ are each independently of one another hydrogen, C₁-C₁₈alkyl or C₇-C₉phenylalkyl, or R₂₉ and R₃₀ together with the nitrogen atom to which they are attached form a 5-, 6- or 7-membered heterocyclic ring,

[0109] X₁ is a direct bond, C₁-C₁₂alkylene, C₂-C₁₈alkylene which is interrupted by oxygen or sulfur;

[0110] C₂-C₁₂alkenylene, C₂-C₁₂alkylidene, C₇-C₁₂phenylalkylidene, C₅-C₈cycloalkylene, phenylene,

[0111] X₂ is C₂-C₁₂alkylene, C₄-C₁₂alkylene which is interrupted by oxygen, sulfur or

[0112] C₂-C₁₂alkenylene, C₅-C₈cycloalkylene, phenylene,

[0113] X₃ is C₂-C₁₈alkylene, C₄-C₁₂alkylene which is interrupted by oxygen, sulfur or

[0114] C₂-C₁₂alkenylene, C₅-C₈cycloalkylene, phenylene,

[0115] ,

[0116] M is a metal cation of valency r,

[0117] n is 1 or 2,

[0118] p is 0, 1 or 2,

[0119] q is 1, 2, 3, 4, 5 or 6, and

[0120] r is 1, 2 or 3.

[0121] Further preferred compounds of the formula I are those wherein,

[0122] when n is 1,

[0123] R₁ is a radical of the formula II, III or IV, and

[0124] when n is 2,

[0125] R₁ is

[0126] R₂, R₃, R₄ and R₅ are each independently of one another hydrogen, C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, cyclohexyl, C₁-C₁₂alkoxy, C₁-C₁₂alkylthio, C₁-C₁₂alkanoyloxy, C₃-C₁₂alkenoyloxy, C₃-C₁₂alkanoyloxy which is interrupted by oxygen; cyclohexylcarbonyloxy, benzoyloxy or each pair of substituents R₂ and R₃ or R₃ and R₄ or R₄ and R₅ together with the linking carbon atoms, forms a benzene ring; or R₄ is additionally —(CH₂)_(p)—COR₁₉ or —(CH₂)_(q)OH, or when R₃, R₅ and R₆ are hydrogen, R₄ is additionally a radical of the formula V, wherein R₁ is as defined above for n=1,

[0127] R₆ is hydrogen or a radical of the formula VI in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1,

[0128] R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ and R₁₅ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₄alkyl; —CN,

[0129] —SOR₂₆, —SO₂R₂₆ or SO₃R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ or R₁₅ is not hydrogen,

[0130] R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene,

[0131] R₁₉ is hydroxyl, C₁-C₁₈alkoxy or

[0132] R₂₀ and R₂₁ are each independently of one another hydrogen, CF₃ or C₁-C₄alkyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a cyclohexylidene ring;

[0133] R₂₂ is hydroxyl, C₁-C₁₂alkyl, phenyl, cyclohexyl or C₃-C₁₂alkyl which is interrupted by oxygen,

[0134] R₂₃ is C₁-C₂₂alkyl, benzyl, phenyl, cyclohexyl or C₃-C₁₂alkyl which is interrupted by oxygen,

[0135] R₂₄ and R₂₅ are each independently of one another hydrogen, C₁-C₁₂alkyl, hydroxyl-substituted C₂-C₁₂alkyl; C₃-C₁₂alkyl which is interrupted by oxygen; benzyl or C₃-C₁₂alkenyl; or R₂₄ and R₂₅, together with the nitrogen atom to which they are attached, form 6-membered heterocyclic ring,

[0136] R₂₆ is C₁-C₁₂alkyl,

[0137] R₂₇ and R₂₈ are each independently of one another hydrogen, C₁-C₁₂alkyl, hydroxyl-substituted C₂-C₁₂alkyl; C₃-C₁₈alkyl which is interrupted by oxygen; benzyl or C₃-C₁₂alkenyl; or R₂₇ and R₂₈, together with the nitrogen atom to which they are attached, form 6-membered heterocyclic ring,

[0138] R₂₉ and R₃₀ are each independently of one another hydrogen, C₁-C₁₂alkyl or benzyl, or R₂₉ and R₃₀ together with the nitrogen atom to which they are attached form a 6-membered heterocyclic ring,

[0139] X₁ is a direct bond, C₁-C₈alkylene, C₂-C₁₈alkylene which is interrupted by oxygen; phenylene,

[0140] or —O—X₃—O—,

[0141] X₂ is C₂-C₈alkylene, C₄-C₁₂alkylene which is interrupted by oxygen; cyclohexylene, phenylene,

[0142] X₃ is C₂-C₁₈alkylene, C₄-C₁₂alkylene which is interrupted by oxygen; C₂-C₁₂alkenylene, cyclohexylene, phenylene,

[0143] n is 1 or 2,

[0144] p is 1 or 2, and

[0145] q is 2 or 3.

[0146] Also preferred are compounds of the formula I

[0147] wherein, when n is 1,

[0148] R₁ is a radical of the formula II, and

[0149] when n is 2,

[0150] R₁ is

[0151] R₂ is hydrogen, C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, cyclohexyl, C₁-C₈alkanoyloxy or benzoyloxy,

[0152] R₃ is hydrogen or C₁-C₄alkyl,

[0153] R₄ is hydrogen, C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, cyclohexyl, C₁-C₈alkanoyloxy, —(CH₂)_(p)—COR₁₉ or —(CH₂)_(q)OH, or when R₃, R₅ and R₆ are hydrogen, R₄ is additionally a radical of the formula V, wherein R₁ is as defined above for n=1,

[0154] R₅ is hydrogen or C₁-C₄alkyl,

[0155] R₆ is hydrogen or a radical of the formula VI in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1,

[0156] R₇, R₈, R₉, R₁₀ and R₁₁ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₄alkyl; —CN,

[0157] —SOR₂₆, or —SO₂R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀ or R₁₁ is not hydrogen,

[0158] R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene,

[0159] R₁₉ is C₁-C₈alkoxy,

[0160] R₂₀ and R₂₁ are each independently of one another hydrogen, CF₃ or C₁-C₄alkyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a cyclohexylidene ring;

[0161] R₂₃ is C₁-C₂₂alkyl, benzyl, phenyl, cyclohexyl or C₃-C₁₂alkyl which is interrupted by oxygen,

[0162] R₂₄ and R₂₅ are each independently of one another hydrogen, C₁-C₄alkyl, hydroxyl-substituted C₂-C₄alkyl; C₃-C₁₂alkyl which is interrupted by oxygen; benzyl or C₃-C₁₂alkenyl,

[0163] R₂₆ is C₁-C₈alkyl,

[0164] R₂₉ and R₃₀ are each independently of one another hydrogen, C₁-C₈alkyl or benzyl,

[0165] X₁ is a direct bond, C₁-C₈alkylene,

[0166] or —O—X₃—O—,

[0167] X₂ is C₂-C₈alkylene or C₄-C₁₂alkylene which is interrupted by oxygen,

[0168] X₃ is C₂-C₁₈alkylene or C₄-C₁₂alkylene which is interrupted by oxygen,

[0169] n is 1 or 2,

[0170] p is 1 or 2, and

[0171] q is 2 or 3.

[0172] Particularly interesting compounds of the formula I are those wherein,

[0173] when n is 1,

[0174] R₁ is a radical of the formula II, and

[0175] when n is 2,

[0176] R₁ is

[0177] R₂ is C₁-C₁₉alkyl, C₇-C₉phenylalkyl, phenyl or cyclohexyl,

[0178] R₃ is hydrogen or methyl,

[0179] R₄ is hydrogen, C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, cyclohexyl or a radical of the formula V, wherein R₁ is as defined above for n=1,

[0180] R₅ is hydrogen or methyl,

[0181] R₆ is hydrogen or a radical of the formula VI in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1,

[0182] R₇, R₈, R₉, R₁₀ and R₁₁ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₄alkyl; —CN,

[0183] —SOR₂₆, or —SO₂R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀ or R₁₁ is not hydrogen,

[0184] R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene,

[0185] R₂₀ and R₂₁ are each independently of one another hydrogen or C₁-C₄alkyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a cyclohexylidene ring;

[0186] R₂₃ is C₁-C₂₂alkyl, benzyl, phenyl, cyclohexyl or C₃-C₁₂alkyl which is interrupted by oxygen,

[0187] R₂₆ is C₁-C₈alkyl,

[0188] X₁ is a direct bond, C₁-C₈alkylene or —O—X₃—O—,

[0189] X₃ is C₂-C₁₈alkylene or C₄-C₁₂alkylene which is interrupted by oxygen, and

[0190] n is 1 or 2.

[0191] Compounds of the formula I of very particular interest are those wherein,

[0192] when n is 1,

[0193] R₁ is a radical of the formula II, and

[0194] when n is 2,

[0195] R₁ is

[0196] R₂ is C₁-C₈alkyl or cyclohexyl,

[0197] R₃ is hydrogen,

[0198] R₄ is hydrogen, C₁-C₈alkyl, cyclohexyl or a radical of the formula V, wherein R₁ is as defined above for n=1,

[0199] R₅ is hydrogen,

[0200] R₆ is hydrogen or a radical of the formula VI in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1,

[0201] R₇, R₈, R₉, R₁₀ and R₁₁ are each independently of one another hydrogen, fluoro, trifluoromethyl; —CN or

[0202] with the proviso that at least one of R₇, R₈, R₉, R₁₀ or R₁₁ is not hydrogen,

[0203] R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene,

[0204] R₂₀ and R₂₁ are each independently of one another hydrogen or C₁-C₄alkyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a cyclohexylidene ring;

[0205] R₂₃ is C₁-C₂₂alkyl, benzyl or cyclohexyl,

[0206] X₁ is C₁-C₈alkylene or —O—X₃—O—,

[0207] X₃ is C₂-C₁₄alkylene, and

[0208] n is 1 or 2.

[0209] Very particularly preferred compounds of the formula I are those wherein

[0210] when n is 1,

[0211] R₁ is a radical of the formula II, and

[0212] when n is 2,

[0213] R₁ is

[0214] R₂ is C₁-C₄alkyl,

[0215] R₃ is hydrogen,

[0216] R₄ is C₁-C₄alkyl,

[0217] R₅ is hydrogen,

[0218] R₆ is hydrogen or a radical of the formula VI wherein R₁ is as defined above for n=1,

[0219] R₇ is hydrogen or trifluoromethyl,

[0220] R₈ is hydrogen, trifluoromethyl or —CN,

[0221] R₉ is hydrogen or trifluoromethyl,

[0222] R₁₀ is hydrogen, trifluoromethyl or —CN,

[0223] R₁₁ is hydrogen, fluoro, trifluoromethyl, —CN or

[0224] with the proviso that at least one of R₇, R₈, R₉, R₁₀ or R₁₁ is not hydrogen,

[0225] R₁₆ and R₁₇ are phenylene or naphthylene,

[0226] R₂₃ is C₁-C₂₂alkyl,

[0227] X₁ is —O—X₃—O—,

[0228] X₃ is C₄-C₁₂alkylene, and

[0229] n is 1 or 2.

[0230] The compounds of the formula I can be prepared in per se known manner. A preferred process for the preparation of the compounds of the formula I is disclosed in WO-A-99/67232.

[0231] The compounds of the formula I are suitable for stabilizing organic materials against oxidative, thermal or light-induced degradation. Special attention is drawn to their excellent action as antioxidants in the stabilization of organic materials.

[0232] Illustrative examples of such materials are:

[0233] 1. Polymers of monoolefins and diolefins, for example polypropylene, polyisobutylene, polybut-1-ene, poly-4-methylpent-1-ene, polyvinylcyclohexane, polyisoprene or polybutadiene, as well as polymers of cycloolefins, for instance of cyclopentene or norbornene, polyethylene (which optionally can be crosslinked), for example high density polyethylene (HDPE), high density and high molecular weight polyethylene (HDPE-HMW), high density and ultrahigh molecular weight polyethylene (HDPE-UHMW), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), (VLDPE) and (ULDPE).

[0234] Polyolefins, i.e. the polymers of monoolefins exemplified in the preceding paragraph, preferably polyethylene and polypropylene, can be prepared by different, and especially by the following, methods:

[0235] a) radical polymerisation (normally under high pressure and at elevated temperature).

[0236] b) catalytic polymerisation using a catalyst that normally contains one or more than one metal of groups IVb, Vb, VIb or VIII of the Periodic Table. These metals usually have one or more than one ligand, typically oxides, halides, alcoholates, esters, ethers, amines, alkyls, alkenyls and/or aryls that may be either π- or σ-coordinated. These metal complexes may be in the free form or fixed on substrates, typically on activated magnesium chloride, titanium(III) chloride, alumina or silicon oxide. These catalysts may be soluble or insoluble in the polymerisation medium. The catalysts can be used by themselves in the polymerisation or further activators may be used, typically metal alkyls, metal hydrides, metal alkyl halides, metal alkyl oxides or metal alkyloxanes, said metals being elements of groups Ia, IIa and/or IIIa of the Periodic Table. The activators may be modified conveniently with further ester, ether, amine or silyl ether groups. These catalyst systems are usually termed Phillips, Standard Oil Indiana, Ziegler (-Natta), TNZ (DuPont), metallocene or single site catalysts (SSC).

[0237] 2. Mixtures of the polymers mentioned under 1), for example mixtures of polypropylene with polyisobutylene, polypropylene with polyethylene (for example PP/HDPE, PP/LDPE) and mixtures of different types of polyethylene (for example LDPE/HDPE).

[0238] 3. Copolymers of monoolefins and diolefins with each other or with other vinyl monomers, for example ethylene/propylene copolymers, linear low density polyethylene (LLDPE) and mixtures thereof with low density polyethylene (LDPE), propylene/but-1-ene copolymers, propylene/isobutylene copolymers, ethylene/but-1-ene copolymers, ethylene/hexene copolymers, ethylene/methylpentene copolymers, ethylene/heptene copolymers, ethylene/octene copolymers, ethylene/vinylcyclohexane copolymers, ethylene/cycloolefin copolymers (e.g. ethylene/norbornene like COC), ethylene/1-olefins copolymers, where the 1-olefin is generated in-situ; propylene/butadiene copolymers, isobutylene/isoprene copolymers, ethylene/vinylcyclohexene copolymers, ethylene/alkyl acrylate copolymers, ethylene/alkyl methacrylate copolymers, ethylene/vinyl acetate copolymers or ethylene/acrylic acid copolymers and their salts (ionomers) as well as terpolymers of ethylene with propylene and a diene such as hexadiene, dicyclopentadiene or ethylidene-norbornene; and mixtures of such copolymers with one another and with polymers mentioned in 1) above, for example polypropylene/ethylene-propylene copolymers, LDPE/ethylene-vinyl acetate copolymers (EVA), LDPE/ethylene-acrylic acid copolymers (EAA), LLDPE/EVA, LLDPE/EAA and alternating or random polyalkylene/carbon monoxide copolymers and mixtures thereof with other polymers, for example polyamides.

[0239] 4. Hydrocarbon resins (for example C₅-C₉) including hydrogenated modifications thereof (e.g. tackifiers) and mixtures of polyalkylenes and starch.

[0240] Homopolymers and copolymers from 1.)-4.) may have any stereostructure including syndiotactic, isotactic, hemi-isotactic or atactic; where atactic polymers are preferred. Stereoblock polymers are also included.

[0241] 5. Polystyrene, poly(p-methylstyrene), poly(α-methylstyrene).

[0242] 6. Aromatic homopolymers and copolymers derived from vinyl aromatic monomers including styrene, α-methylstyrene, all isomers of vinyl toluene, especially p-vinyltoluene, all isomers of ethyl styrene, propyl styrene, vinyl biphenyl, vinyl naphthalene, and vinyl anthracene, and mixtures thereof. Homopolymers and copolymers may have any stereostructure including syndiotactic, isotactic, hemi-isotactic or atactic; where atactic polymers are preferred. Stereoblock polymers are also included.

[0243] 6a. Copolymers including aforementioned vinyl aromatic monomers and comonomers selected from ethylene, propylene, dienes, nitriles, acids, maleic anhydrides, maleimides, vinyl acetate and vinyl chloride or acrylic derivatives and mixtures thereof, for example styrene/butadiene, styrene/acrylonitrile, styrene/ethylene (interpolymers), styrene/alkyl methacrylate, styrene/butadiene/alkyl acrylate, styrene/butadiene/alkyl methacrylate, styrene/maleic anhydride, styrene/acrylonitrile/methyl acrylate; mixtures of high impact strength of styrene copolymers and another polymer, for example a polyacrylate, a diene polymer or an ethylene/propylene/diene terpolymer; and block copolymers of styrene such as styrene/butadiene/styrene, styrene/isoprene/styrene, styrene/ethylene/butylene/styrene or styrene/ethylene/propylene/styrene.

[0244] 6b. Hydrogenated aromatic polymers derived from hydrogenation of polymers mentioned under 6.), especially including polycyclohexylethylene (PCHE) prepared by hydrogenating atactic polystyrene, often referred to as polyvinylcyclohexane (PVCH).

[0245] 6c. Hydrogenated aromatic polymers derived from hydrogenation of polymers mentioned under 6a.).

[0246] Homopolymers and copolymers may have any stereostructure including syndiotactic, isotactic, hemi-isotactic or atactic; where atactic polymers are preferred. Stereoblock polymers are also included.

[0247] 7. Graft copolymers of vinyl aromatic monomers such as styrene or α-methylstyrene, for example styrene on polybutadiene, styrene on polybutadiene-styrene or polybutadiene-acrylonitrile copolymers; styrene and acrylonitrile (or methacrylonitrile) on polybutadiene; styrene, acrylonitrile and methyl methacrylate on polybutadiene; styrene and maleic anhydride on polybutadiene; styrene, acrylonitrile and maleic anhydride or maleimide on polybutadiene; styrene and maleimide on polybutadiene; styrene and alkyl acrylates or methacrylates on polybutadiene; styrene and acrylonitrile on ethylene/propylene/diene terpolymers; styrene and acrylonitrile on polyalkyl acrylates or polyalkyl methacrylates, styrene and acrylonitrile on acrylate/butadiene copolymers, as well as mixtures thereof with the copolymers listed under 6), for example the copolymer mixtures known as ABS, MBS, ASA or AES polymers.

[0248] 8. Halogen-containing polymers such as polychloroprene, chlorinated rubbers, chlorinated and brominated copolymer of isobutylene-isoprene (halobutyl rubber), chlorinated or sulfochlorinated polyethylene, copolymers of ethylene and chlorinated ethylene, epichlorohydrin homo- and copolymers, especially polymers of halogen-containing vinyl compounds, for example polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, polyvinylidene fluoride, as well as copolymers thereof such as vinyl chloride/vinylidene chloride, vinyl chloride/vinyl acetate or vinylidene chloride/vinyl acetate copolymers.

[0249] 9. Polymers derived from α,β-unsaturated acids and derivatives thereof such as polyacrylates and polymethacrylates; polymethyl methacrylates, polyacrylamides and polyacrylonitriles, impact-modified with butyl acrylate.

[0250] 10. Copolymers of the monomers mentioned under 9) with each other or with other unsaturated monomers, for example acrylonitrile/butadiene copolymers, acrylonitrile/alkyl acrylate copolymers, acrylonitrile/alkoxyalkyl acrylate or acrylonitrile/vinyl halide copolymers or acrylonitrile/alkyl methacrylate/butadiene terpolymers.

[0251] 11. Polymers derived from unsaturated alcohols and amines or the acyl derivatives or acetals thereof, for example polyvinyl alcohol, polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinyl butyral, polyallyl phthalate or polyallyl melamine; as well as their copolymers with olefins mentioned in 1) above.

[0252] 12. Homopolymers and copolymers of cyclic ethers such as polyalkylene glycols, polyethylene oxide, polypropylene oxide or copolymers thereof with bisglycidyl ethers.

[0253] 13. Polyacetals such as polyoxymethylene and those polyoxymethylenes which contain ethylene oxide as a comonomer; polyacetals modified with thermoplastic polyurethanes, acrylates or MBS.

[0254] 14. Polyphenylene oxides and sulfides, and mixtures of polyphenylene oxides with styrene polymers or polyamides.

[0255] 15. Polyurethanes derived from hydroxyl-terminated polyethers, polyesters or polybutadienes on the one hand and aliphatic or aromatic polyisocyanates on the other, as well as precursors thereof.

[0256] 16. Polyamides and copolyamides derived from diamines and dicarboxylic acids and/or from aminocarboxylic acids or the corresponding lactams, for example polyamide 4, polyamide 6, polyamide 6/6, 6/10, 6/9, 6/12, 4/6, 12/12, polyamide 11, polyamide 12, aromatic polyamides starting from m-xylene diamine and adipic acid; polyamides prepared from hexamethylenediamine and isophthalic or/and terephthalic acid and with or without an elastomer as modifier, for example poly-2,4,4,-trimethylhexamethylene terephthalamide or poly-m-phenylene isophthalamide; and also block copolymers of the aforementioned polyamides with polyolefins, olefin copolymers, ionomers or chemically bonded or grafted elastomers; or with polyethers, e.g. with polyethylene glycol, polypropylene glycol or polytetramethylene glycol; as well as polyamides or copolyamides modified with EPDM or ABS; and polyamides condensed during processing (RIM polyamide systems).

[0257] 17. Polyureas, polyimides, polyamide-imides, polyetherimids, polyesterimids, polyhydantoins and polybenzimidazoles.

[0258] 18. Polyesters derived from dicarboxylic acids and diols and/or from hydroxycarboxylic acids or the corresponding lactones, for example polyethylene terephthalate, polybutylene terephthalate, poly-1,4-dimethylolcyclohexane terephthalate, polyalkylene naphthalate (PAN) and polyhydroxybenzoates, as well as block copolyether esters derived from hydroxyl-terminated polyethers; and also polyesters modified with polycarbonates or MBS.

[0259] 19. Polycarbonates and polyester carbonates.

[0260] 20. Polysulfones, polyether sulfones and polyether ketones.

[0261] 21. Crosslinked polymers derived from aldehydes on the one hand and phenols, ureas and melamines on the other hand, such as phenol/formaldehyde resins, urea/formaldehyde resins and melamine/formaldehyde resins.

[0262] 22. Drying and non-drying alkyd resins.

[0263] 23. Unsaturated polyester resins derived from copolyesters of saturated and unsaturated dicarboxylic acids with polyhydric alcohols and vinyl compounds as crosslinking agents, and also halogen-containing modifications thereof of low flammability.

[0264] 24. Crosslinkable acrylic resins derived from substituted acrylates, for example epoxy acrylates, urethane acrylates or polyester acrylates.

[0265] 25. Alkyd resins, polyester resins and acrylate resins crosslinked with melamine resins, urea resins, isocyanates, isocyanurates, polyisocyanates or epoxy resins.

[0266] 26. Crosslinked epoxy resins derived from aliphatic, cycloaliphatic, heterocyclic or aromatic glycidyl compounds, e.g. products of diglycidyl ethers of bisphenol A and bisphenol F, which are crosslinked with customary hardeners such as anhydrides or amines, with or without accelerators.

[0267] 27. Natural polymers such as cellulose, rubber, gelatin and chemically modified homologous derivatives thereof, for example cellulose acetates, cellulose propionates and cellulose butyrates, or the cellulose ethers such as methyl cellulose; as well as rosins and their derivatives.

[0268] 28. Blends of the aforementioned polymers (polyblends), for example PP/EPDM, Polyamide/EPDM or ABS, PVC/EVA, PVC/ABS, PVC/MBS, PC/ABS, PBTP/ABS, PC/ASA, PC/PBT, PVC/CPE, PVC/acrylates, POM/thermoplastic PUR, PC/thermoplastic PUR, POM/acrylate, POM/MBS, PPO/HIPS, PPO/PA 6.6 and copolymers, PA/HDPE, PA/PP, PA/PPO, PBT/PC/ABS or PBT/PET/PC.

[0269] 29. Naturally occurring and synthetic organic materials which are pure monomeric compounds or mixtures of such compounds, for example mineral oils, animal and vegetable fats, oil and waxes, or oils, fats and waxes based on synthetic esters (e.g. phthalates, adipates, phosphates or trimellitates) and also mixtures of synthetic esters with mineral oils in any weight ratios, typically those used as spinning compositions, as well as aqueous emulsions of such materials.

[0270] 30. Aqueous emulsions of natural or synthetic rubber, e.g. natural latex or latices of carboxylated styrene/butadiene copolymers.

[0271] Further objects of the invention are therefore compositions comprising a) an organic material that is susceptible to oxidative, thermal or light-induced degradation, and b) at least one compound of the formula I.

[0272] Preferred organic materials are natural, semi-synthetic or, preferably, synthetic polymers.

[0273] Particularly referred organic materials are synthetic polymers, most preferably thermoplastic polymers. Especially preferred organic materials are polyacetals, polyolefins such as polypropylene or polyethylene, polyether/polyurethanes, polyesters such as polybutylene terephthalate, polycarbonates or vulcanisates,

[0274] To be singled out for special mention is the efficacy of the novel compounds of the formula I against oxidative or thermal degradation, especially under the action of heat which occurs during the processing of thermoplasts. The compounds of the formula I of this invention are therefore admirably suited for use as processing stabilizers.

[0275] The compounds of the formula I will preferably be added to the organic material to be stabilized in concentrations of 0.0005 to 10%, preferably 0.001 to 2%, typically 0.01 to 2%, based on the weight of said material.

[0276] In addition to comprising the compounds of the formula I, the inventive compositions may comprise further co-stabilizers, typically the following:

[0277] 1. Antioxidants

[0278] 1.1. Alkylated monophenols, for example 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-di-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4-methylphenol, 2-(α-methylcyclohexyl)-4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6-tricyclohexylphenol, 2,6-di-tert-butyl-4-methoxymethylphenol, nonylphenols which are linear or branched in the side chains, for example 2,6-di-nonyl-4-methylphenol, 2,4-dimethyl-6-(1′-methylundec-1′-yl)phenol, 2,4-dimethyl-6-(1′-methylheptadec-1′-yl)phenol, 2,4-dimethyl-6-(1′-methyltridec-1′-yl)phenol and mixtures thereof.

[0279] 1.2. Alkylthiomethylphenols, for example 2,4-dioctylthiomethyl-6-tert-butylphenol, 2,4-dioctylthiomethyl-6-methylphenol, 2,4-dioctylthiomethyl-6-ethylphenol, 2,6-di-dodecylthiomethyl-4-nonylphenol.

[0280] 1.3. Hydroquinones and alkylated hydroquinones, for example 2,6-di-tert-butyl-4-methoxyphenol, 2,5-di-tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone, 2,6-diphenyl-4-octadecyloxyphenol, 2,6-di-tert-butylhydroquinone, 2,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyphenyl stearate, bis(3,5-di-tert-butyl-4-hydroxyphenyl) adipate.

[0281] 1.4. Tocopherols, for example α-tocopherol, β-tocopherol, γ-tocopherol, δ-tocopherol and mixtures thereof (vitamin E).

[0282] 1.5. Hydroxylated thiodiphenyl ethers, for example 2,2′-thiobis(6-tert-butyl-4-methylphenol), 2,2′-thiobis(4-octylphenol), 4,4′-thiobis(6-tert-butyl-3-methylphenol), 4,4′-thiobis(6-tert-butyl-2-methylphenol), 4,4′-thiobis(3,6-di-sec-amylphenol), 4,4′-bis(2,6-dimethyl-4-hydroxyphenyl)-disulfide.

[0283] 1.6. Alkylidenebisphenols, for example 2,2′-methyienebis(6-tert-butyl-4-methylphenol), 2,2′-methylenebis(6-tert-butyl-4-ethylphenol), 2,2′-methylenebis[4-methyl-6-(α-methylcyclohexyl)-phenol], 2,2′-methylenebis(4-methyl-6-cyclohexylphenol), 2,2′-methylenebis(6-nonyl-4-methylphenol), 2,2′-methylenebis(4,6-di-tert-butylphenol), 2,2′-ethylidenebis(4,6-di-tert-butyl-phenol), 2,2′-ethylidenebis(6-tert-butyl-4-isobutylphenol), 2,2′-methylenebis[6-(α-methylbenzyl)-4-nonylphenol], 2,2′-methylenebis[6-(α,α-dimethylbenzyl)-4-nonylphenol], 4,4′-methylenebis(2,6-di-tert-butylphenol), 4,4′-methylenebis(6-tert-butyl-2-methylphenol), 1,1-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)butane, 2,6-bis(3-tert-butyl-5-methyl-2-hydroxybenzyl)-4-methylphenol, 1,1,3-tris(5-tert-butyl-4-hydroxy-2-methylphenyl)butane, 1,1-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)-3-n-dodecylmercaptobutane, ethylene glycol bis[3,3-bis(3′-tert-butyl-4′-hydroxyphenyl)butyrate], bis(3-tert-butyl-4-hydroxy-5-methyl-phenyl)dicyclopentadiene, bis[2-(3′-tert-butyl-2′-hydroxy-5′-methylbenzyl)-6-tert-butyl-4-methylphenyl]terephthalate, 1,1-bis-(3,5-dimethyl-2-hydroxyphenyl)butane, 2,2-bis(3,5-di-tert-butyl-4-hydroxyphenyl)propane, 2,2-bis-(5-tert-butyl-4-hydroxy2-methylphenyl)-4-n-dodecylmercaptobutane, 1,1,5,5-tetra(5-tert-butyl-4-hydroxy-2-methylphenyl)pentane.

[0284] 1.7. O-, N- and S-benzyl compounds, for example 3,5,3′,5′-tetra-tert-butyl-4,4′-dihydroxydibenzyl ether, octadecyl-4-hydroxy-3,5-dimethylbenzylmercaptoacetate, tridecyl-4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate, tris(3,5-di-tert-butyl-4-hydroxybenzyl)amine, bis(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)dithioterephthalate, bis(3,5-di-tert-butyl-4-hydroxy-benzyl)sulfide, isooctyl-3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate.

[0285] 1.8. Hydroxybenzylated malonates, for example dioctadecyl-2,2-bis(3,5-di-tert-butyl-2-hydroxybenzyl)malonate, di-octadecyl-2-(3-tert-butyl-4-hydroxy-5-methylbenzyl)malonate, didodecylmercaptoethyl-2,2-bis(3,5-di-tert-butyl-4-hydroxybenzyl)malonate, bis[4-(1,1,3,3-tetramethylbutyl)phenyl]-2,2-bis(3,5-di-tert-butyl-4-hydroxybenzyl)malonate.

[0286] 1.9. Aromatic hydroxybenzyl compounds, for example 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene, 1,4-bis(3,5-di-tert-butyl-4-hydroxybenzyl)-2,3,5,6-tetramethylbenzene, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)phenol.

[0287] 1.10. Triazine compounds, for example 2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,3,5-triazine, 2,4,6-tris-(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,2,3-triazine, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate, 2,4,6-tris-(3,5-di-tert-butyl-4-hydroxyphenylethyl)-1,3,5-triazine, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxy-phenylpropionyl)-hexahydro-1,3,5-triazine, 1,3,5-tris(3,5-dicyclohexyl-4-hydroxybenzyl)isocyanurate.

[0288] 1.11. Benzylphoshonates, for example dimethyl-2,5-di-tert-butyl-4-hydroxybenzylphosphonate, diethyl-3,5-di-tert-butyl-4-hydroxybenzylphosphonate, dioctadecyl3,5-di-tert-butyl-4-hydroxybenzylphosphonate, dioctadecyl-5-tert-butyl-4-hydroxy-3-methylbenzylphosphonate, the calcium salt of the monoethyl ester of 3,5-di-tert-butyl-4-hydroxybenzylphosphonic acid.

[0289] 1.12. Acylaminophenols, for example 4-hydroxylauranilide, 4-hydroxystearanilide, octyl N-(3,5-di-tert-butyl-4-hydroxyphenyl)carbamate.

[0290] 1.13. Esters of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, n-octanol, i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

[0291] 1.14. Esters of β-(5-tert-butyl-4-hydroxy-3-methylphenyl)propionic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, n-octanol, i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N′-bis-(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane; 3,9-bis[2-{3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy}-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]-undecane.

[0292] 1.15. Esters of β-(3,5-dicyclohexyl-4-hydroxyphenyl)propionic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

[0293] 1.16. Esters of 3,5-di-tert-butyl-4-hydroxaphenyl acetic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

[0294] 1.17. Amides of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid e.g. N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hexamethylenediamide, N,N′-bis(3,5-di-tert-butyl-4-hydroxy-phenylpropionyl)trimethylenediamide, N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hydrazide, N,N′-bis[2-(3-[3,5-di-tert-butyl-4-hydroxyphenylpropionyloxy)ethyl]oxamide (Naugard®XL-1, supplied by Uniroyal).

[0295] 1.18. Ascorbic acid (vitamin C)

[0296] 1.19. Aminic antioxidants, for example N,N′-di-isopropyl-p-phenylenediamine, N,N′-di-sec-butyl-p-phenylenediamine, N,N′-bis(1,4-dimethylpentyl)-p-phenylenediamine, N,N′-bis(1-ethyl-3-methylpentyl)-p-phenylenediamine, N,N′-bis(1-methylheptyl)-p-phenylenediamine, N,N′-dicyclohexyl-p-phenylenediamine, N,N′-diphenyl-p-phenylenediamine, N,N′-bis(2-naphthyl)-p-phenylenediamine, N-isopropyl-N′-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine, N-(1-methylheptyl)-N′-phenyl-p-phenylenediamine, N-cyclohexyl-N′-phenyl-p-phenylenediamine, 4-(p-toluenesulfamoyl)diphenylamine, N,N′-dimethyl-N,N′-di-sec-butyl-p-phenylenediamine, diphenylamine, N-allyldiphenylamine, 4-isopropoxydiphenylamine, N-phenyl-1-naphthylamine, N-(4-tert-octylphenyl)-1-naphthylamine, N-phenyl-2-naphthylamine, octylated diphenylamine, for example p,p′-di-tert-octyldiphenylamine, 4-n-butylaminophenol, 4-butyrylaminophenol, 4-nonanoylaminophenol, 4-dodecanoylaminophenol, 4-octadecanoylaminophenol, bis(4-methoxyphenyl)amine, 2,6-di-tert-butyl-4-dimethylaminomethylphenol, 2,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, N,N,N′,N′-tetramethyl-4,4′-diaminodiphenylmethane, 1,2-bis[(2-methylphenyl)amino]ethane, 1,2-bis(phenylamino)propane, (o-tolyl)biguanide, bis[4-(1′,3′-dimethylbutyl)phenyl]amine, tert-octylated N-phenyl-1-naphthylamine, a mixture of mono- and dialkylated tert-butyl/tert-octyldiphenylamines, a mixture of mono- and dialkylated nonyidiphenylamines, a mixture of mono- and dialkylated dodecyidiphenylamines, a mixture of mono- and dialkylated isopropyl/isohexyldiphenylamines, a mixture of mono- and dialkylated tert-butyldiphenylamines, 2,3-dihydro-3,3-dimethyl-4H-1,4-benzothiazine, phenothiazine, a mixture of mono- and dialkylated tert-butyl/tert-octylphenothiazines, a mixture of mono- and dialkylated tert-octylphenothiazines, N-allylphenothiazine, N,N,N′,N′-tetraphenyl-1,4-diaminobut-2-ene, N,N-bis(2,2,6,6-tetra-methylpiperid-4-yl-hexamethylenediamine, bis(2,2,6,6-tetramethylpiperid-4-yl)sebacate, 2,2,6,6-tetramethylpiperidin-4-one, 2,2,6,6-tetramethylpiperidin-4-ol.

[0297] 2. UV Absorbers and Light Stabilizers

[0298] 2.1. 2-(2′-Hydroxyphenyl)benzotriazoles, for example 2-(2′-hydroxy-5′-methylphenyl)benzotriazole, 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(5′-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(2′-hydroxy-5′-(1,1,3,3-tetramethylbutyl)phenyl)benzotriazole, 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-methylphenyl)-5-chlorobenzotriazole, 2-(3′-sec-butyl-5′-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(2′-hydroxy-4′-octyloxyphenyl)benzotriazole, 2-(3′,5′-di-tert-amyl-2′-hydroxyphenyl)benzotriazole, 2-(3′,5′-bis(α,α-dimethylbenzyl)-2′-hydroxyphenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)-5-chlorobenzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)benzotriazole, 2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxyphenyl)benzotriazole, 2-(3′-dodecyl-2′-hydroxy-5′-methylphenyl)benzotriazole, 2-(3′-tert-butyl-2′-hydroxy-5′-(2-isooctyloxycarbonylethyl)phenylbenzotriazole, 2,2′-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-benzotriazole-2-ylphenol]; the transesterification product of 2-[3′-tert-butyl-5′-(2-methoxycarbonylethyl)-2′-hydroxyphenyl]-2H-benzotriazole with polyethylene glycol 300;

[0299] where R=3′-tert-butyl-4′-hydroxy-5′-2H-benzotriazol-2-ylphenyl, 2-[2′-hydroxy-3′-(α,α-dimethylbenzyl)-5′-(1,1,3,3-tetramethylbutyl)phenyl]-benzotriazole; 2-[2′-hydroxy-3′-(1,1,3,3-tetramethylbutyl)-5′-(α,α-dimethylbenzyl)phenyl]benzotriazole.

[0300] 2.2. 2-Hydroxybenzophenones, for example the 4-hydroxy, 4-methoxy, 4-octyloxy, 4-decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2′,4′-trihydroxy and 2′-hydroxy-4,4′-dimethoxy derivatives.

[0301] 2.3. Esters of substituted and unsubstituted benzoic acids, for example 4-tert-butylphenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoyl resorcinol, bis(4-tert-butylbenzoyl)resorcinol, benzoyl resorcinol, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, 2-methyl-4,6-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate.

[0302] 2.4. Acrylates, for example ethyl α-cyano-β,β-diphenylacrylate, isooctyl α-cyano-β,β-diphenylacrylate, methyl α-carbomethoxycinnamate, methyl α-cyano-β-methyl-p-methoxycinnamate, butyl α-cyano-β-methyl-p-methoxycinnamate, methyl α-carbomethoxy-p-methoxycinnamate and N-(β-carbomethoxy-β-cyanovinyl)-2-methylindoline.

[0303] 2.5. Nickel compounds, for example nickel complexes of 2,2′-thiobis[4-(1,1,3,3-tetramethylbutyl)phenol], such as the 1:1 or 1:2 complex, with or without additional ligands such as n-butylamine, triethanolamine or N-cyclohexyldiethanolamine, nickel dibutyldithiocarbamate, nickel salts of the monoalkyl esters, e.g. the methyl or ethyl ester, of 4-hydroxy-3,5-di-tert-butylbenzylphosphonic acid, nickel complexes of ketoximes, e.g. of 2-hydroxy-4-methylphenylundecylketoxime, nickel complexes of 1-phenyl-4-lauroyl-5-hydroxypyrazole, with or without additional ligands.

[0304] 2.6. Sterically hindered amines, for example bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)succinate, bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate, the condensate of 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid, linear or cyclic condensates of N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine, tris(2,2,6,6-tetramethyl-4-piperidyl)nitrilotriacetate, tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate, 1,1′-(1,2-ethanediyl)-bis(3,3,5,5-tetramethylpiperazinone), 4-benzoyl-2,2,6,6-tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, bis(1,2,2,6,6-pentamethylpiperidyl)-2-n-butyl-2-(2-hydroxy-3,5-di-tert-butylbenzyl)malonate, 3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione, bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)sebacate, bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)succinate, linear or cyclic condensates of N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-morpholino-2,6-dichloro-1,3,5-triazine, the condensate of 2-chloro-4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane, the condensate of 2-chloro-4,6-di-(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane, 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione, 3-dodecyl-1-(2,2,6,6-tetramethyl-4-piperidyl)pyrrolidine-2,5-dione, 3-dodecyl-1-(1,2,2,6,6-pentamethyl-4-piperidyl)pyrrolidine-2,5-dione, a mixture of 4-hexadecyloxy- and 4-stearyloxy-2,2,6,6-tetramethylpiperidine, a condensate of N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1,3,5-triazine, a condensate of 1,2-bis(3-aminopropylamino)ethane and 2,4,6-trichloro-1,3,5-triazine as well as 4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No. [136504-96-6]); a condensate of 1,6-hexanediamine and 2,4,6-trichloro-1,3,5-triazine as well as N,N-dibutylamine and 4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No. [192268-64-7]); N-(2,2,6,6-tetramethyl-4-piperidyl)-n-dodecylsuccinimide, N-(1,2,2,6,6-pentamethyl-4-piperidyl)-n-dodecylsuccinimide, 2-undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxo-spiro[4,5]decane, a reaction product of 7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro-[4,5]decane and epichlorohydrin, 1,1-bis(1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyl)-2-(4-methoxyphenyl)ethene, N,N′-bis-formyl-N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine, a diester of 4-methoxymethylenemalonic acid with 1,2,2,6,6-pentamethyl-4-hydroxypiperidine, poly[methylpropyl-3-oxy-4-(2,2,6,6-tetramethyl-4-piperidyl)]siloxane, a reaction product of maleic acid anhydride-α-olefin copolymer with 2,2,6,6-tetramethyl-4-aminopiperidine or 1,2,2,6,6-pentamethyl-4-aminopiperidine.

[0305] 2.7. Oxamides, for example 4,4′-dioctyloxyoxanilide, 2,2′-diethoxyoxanilide, 2,2′-dioctyloxy-5,5′-di-tert-butoxanilide, 2,2′-didodecyloxy-5,5′-di-tert-butoxanilide, 2-ethoxy-2′-ethyloxanilide, N,N′-bis(3-dimethylaminopropyl)oxamide, 2-ethoxy-5-tert-butyl-2′-ethoxanilide and its mixture with 2-ethoxy-2′-ethyl-5,4′-di-tert-butoxanilide, mixtures of o- and p-methoxy-disubstituted oxanilides and mixtures of o- and p-ethoxy-disubstituted oxanilides.

[0306] 2.8. 2-(2-Hydroxyphenyl)-1,3,5-triazines, for example 2,4,6-tris(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-dodecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-tridecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[2-hydroxy-4-12-hydroxy-3-butyloxypropoxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-octyloxypropyloxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine, 2-[4-(dodecyloxy/tridecyloxy-2-hydroxypropoxy)-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3-dodecyloxypropoxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(2-hydroxy-4-hexyloxy)phenyl-4,6-diphenyl-1,3,5-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-1,3,5-triazine, 2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxypropoxy)phenyl]-1,3,5-triazine, 2-(2-hydroxyphenyl)-4-(4-methoxyphenyl)-6-phenyl-1,3,5-triazine, 2-{2-hydroxy-4-[3-(2-ethylhexyl-1-oxy)-2-hydroxypropyloxy]phenyl}-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine.

[0307] 3. Metal deactivators, for example N,N′-diphenyloxamide, N-salicylal-N′-salicyloyl hydrazine, N,N′-bis(salicyloyl)hydrazine, N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hydrazine, 3-salicyloylamino-1,2,4-triazole, bis(benzylidene)oxalyl dihydrazide, oxanilide, isophthaloyl dihydrazide, sebacoyl bisphenylhydrazide, N,N′-diacetyladipoyl dihydrazide, N,N′-bis(salicyloyl)oxalyl dihydrazide, N,N′-bis(salicyloyl)thiopropionyl dihydrazide.

[0308] 4. Phosphites and phosphonites, for example triphenyl phosphite, diphenylalkyl phosphites, phenyldialkyl phosphites, tris(nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearylpentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,4-dicumylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, diisodecyloxypentaerythritol diphosphite, bis(2,4-di-tert-butyl-6-methylphenyl)-pentaerythritol diphosphite, bis(2,4,6-tris(tert-butylphenyl)pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis(2,4-di-tert-butylphenyl) 4,4′-biphenylene diphosphonite, 6-isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-dibenz[d,g]-1,3,2-dioxaphosphocin, bis(2,4-di-tert-butyl-6-methylphenyl)methyl phosphite, bis(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphite, 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-dibenz[d,g]-1,3,2-dioxaphosphocin, 2,2′,2″-nitrilo-[triethyltris(3,3′,5,5′-tetra-tert-butyl-1,1′-biphenyl-2,2′-diyl)phosphite], 2-ethylhexyl(3,3′,5,5′-tetra-tert-butyl-1,1′-biphenyl-2,2′-diyl)phosphite, 5-butyl-5-ethyl-2-(2,4,6-tri-tert-butylphenoxy)-1,3,2-dioxaphosphirane.

[0309] 5. Hydroxylamines, for example N,N-dibenzylhydroxylamine, N,N-diethylhydroxylamine, N,N-dioctyihydroxylamine, N,N-dilaurylhydroxylamine, N,N-ditetradecylhydroxylamine, N,N-dihexadecylhydroxylamine, N,N-dioctadecylhydroxylamine, N-hexadecyl-N-octadecylhydroxylamine, N-heptadecyl-N-octadecylhydroxylamine, N,N-dialkylhydroxylamine derived from hydrogenated tallow amine.

[0310] 6. Nitrones, for example N-benzyl-alpha-phenylnitrone, N-ethyl-alpha-methyinitrone, N-octyl-alpha-heptylnitrone, N-lauryl-alpha-undecyinitrone, N-tetradecyl-alpha-tridecylnitrone, N-hexadecyl-alpha-pentadecylnitrone, N-octadecyl-alpha-heptadecylnitrone, N-hexadecyl-alpha-heptadecyinitrone, N-ocatadecyl-alpha-pentadecylnitrone, N-heptadecyl-alpha-heptadecylnitrone, N-octadecyl-alpha-hexadecylnitrone, nitrone derived from N,N-dialkylhydroxylamine derived from hydrogenated tallow amine.

[0311] 7. Thiosynergists, for example dilauryl thiodipropionate or distearyl thiodipropionate.

[0312] 8. Peroxide scavengers, for example esters of β-thiodipropionic acid, for example the lauryl, stearyl, myristyl or tridecyl esters, mercaptobenzimidazole or the zinc salt of 2-mercaptobenzimidazole, zinc dibutyldithiocarbamate, dioctadecyl disulfide, pentaerythritol tetrakis(β-dodecylmercapto)propionate.

[0313] 9. Polyamide stabilizers, for example copper salts in combination with iodides and/or phosphorus compounds and salts of divalent manganese.

[0314] 10. Basic co-stabilizers, for example melamine, polyvinylpyrrolidone, dicyandiamide, triallyl cyanurate, urea derivatives, hydrazine derivatives, amines, polyamides, polyurethanes, alkali metal salts and alkaline earth metal salts of higher fatty acids, for example calcium stearate, zinc stearate, magnesium behenate, magnesium stearate, sodium ricinoleate and potassium palmitate, antimony pyrocatecholate or zinc pyrocatecholate.

[0315] 11. Nucleating agents, for example inorganic substances, such as talcum, metal oxides, such as titanium dioxide or magnesium oxide, phosphates, carbonates or sulfates of, preferably, alkaline earth metals; organic compounds, such as mono- or polycarboxylic acids and the salts thereof, e.g. 4-tert-butylbenzoic acid, adipic acid, diphenylacetic acid, sodium succinate or sodium benzoate; polymeric compounds, such as ionic copolymers (ionomers). Especially preferred are 1,3:2,4-bis(3′,4′-dimethylbenzylidene)sorbitol, 1,3:2,4-di(paramethyldibenzylidene)sorbitol, and 1,3:2,4-di(benzylidene)sorbitol.

[0316] 12. Fillers and reinforcing agents, for example calcium carbonate, silicates, glass fibres, glass bulbs, asbestos, talc, kaolin, mica, barium sulfate, metal oxides and hydroxides, carbon black, graphite, wood flour and flours or fibers of other natural products, synthetic fibers.

[0317] 13. Other additives, for example plasticisers, lubricants, emulsifiers, pigments, rheology additives, catalysts, flow-control agents, optical brighteners, flameproofing agents, antistatic agents and blowing agents.

[0318] 14. Benzofuranones and indolinones, for example those disclosed in U.S. Pat. No. 4,325,863; U.S. Pat. No. 4,338,244; U.S. Pat. No. 5,175,312; U.S. Pat. No. 5,216,052; U.S. Pat. No 5,252,643; DE-A-4316611; DE-A-4316622; DE-A-4316876; EP-A-0589839 or EP-A-0591102 or 3-[4-(2-acetoxyethoxy)-phenyl]-5,7-di-tert-butylbenzofuran-2-one, 5,7-di-tert-butyl-3-[4-(2-stearoyloxyethoxy)phenyl]-benzofuran-2-one, 3,3′-bis[5,7-di-tert-butyl-3-(4-[2-hydroxyethoxy]phenyl)benzofuran-2-one], 5,7-di-tert-butyl-3-(4-ethoxyphenyl)benzofuran-2-one, 3-(4-acetoxy-3,5-dimethylphenyl)-5,7-di-tert-butylbenzofuran-2-one, 3-(3,5-dimethyl-4-pivaloyloxyphenyl)-5,7-di-tert-butylbenzofuran-2-one, 3-(3,4-dimethylphenyl)-5,7-di-tert-butylbenzofuran-2-one, 3-(2,3-dimethylphenyl)-5,7-di-tert-butylbenzofuran-2-one.

[0319] The co-stabilizers are typically used in concentrations of 0.01 to 10%, based on the total weight of the material to be stabilized.

[0320] The novel compounds of the formula I can be used in particular together with phenolic antioxidants, light stabilizers and/or processing stabilizers.

[0321] Other preferred compositions comprise, in addition to compounds of the formula I, a compound of the organic phosphite or phosphonite type.

[0322] The fillers and reinforcing agents (point 12 of the list), such as, for example, talc, calcium carbonate, mica or kaolin, are added to the polyolefins, for example, in concentrations of from 0.01 to 40%, based on the total weight of the polyolefins to be stabilized.

[0323] The fillers and reinforcing agents (point 12 of the list), such as, for example, metal hydroxides, especially aluminium hydroxide or magnesium hydroxide, are added to the polyolefins, for example, in concentrations of from 0.01 to 60%, based on the total weight of the polyolefins to be stabilized.

[0324] Carbon black, as filler, is added to the polyolefins advantageously in concentrations of from 0.01 to 5%, based on the total weight of the polyolefins to be stabilized.

[0325] Glass fibres, as reinforcing agents, are added to the polyolefins advantageously in concentrations of from 0.01 to 20%, based on the total weight of the polyolefins to be stabilized.

[0326] Also of interest as yet further additives in the compositions according to the invention are alkaline earth metal salts of higher fatty acids, such as, for example, calcium stearate; calcium lactate and/or calcium stearoyl-2-lactylate.

[0327] As a conventional stabilizer combination for the processing of polymeric organic materials, such as, for example, polyolefins, into corresponding moulded articles, the combination of a phenolic antioxidant with a secondary antioxidant based on an organic phosphite or phosphonite is recommended. Depending on the substrate and process, however, many polyolefin processors are obliged to operate processes in the high-temperature range above approx. 280° C. The inclusion of a processing stabilizer of the formula I is particularly suitable for high-temperature applications, especially in the temperature range above 300° C. Technical materials and moulded articles for instance based on HD polyethylene, such as, for example, pipes and their technical variants (fittings), can be manufactured with a higher output and fewer rejects. A further advantage of the compounds of the formula I is also that they can be used in a very small amount, which results in a reduction in the overall antioxidant concentration compared with conventional stabilizer mixtures. For instance the use of a low concentration of a compound of the formula I allows the overall stabilizer concentration to be reduced by approximately a third in, for example, polyolefins, which at the same time represents an economic advantage.

[0328] The compounds of the formula I and other optional additives are incorporated into the organic polymeric material according to known methods, for example before or during shaping to moulded articles or alternatively by coating the organic polymeric material with a solution or dispersion of the compounds and subsequently evaporating the solvent. The compounds of the formual I can also be added to the materials to be stabilized in the form of a master batch which contains these compounds, typically in a concentration of, for example, from 2.5 to 25% by weight.

[0329] The compounds of the formula I may also be added before or during polymerization or before crosslinking.

[0330] In this connection, particular attention is drawn to the surprising feature that the novel compounds of the formula I inhibit discoloration, especially so-called pinking in the manufacture of e.g. polyurethane foams.

[0331] The compounds of the formula I, and where applicable further additives, may be incorporated into the material to be stabilized in pure form or encapsulated in waxes, oils or polymers.

[0332] The compounds of the formula I, and where applicable further additives, may also be sprayed onto the polymer to be stabilized. They are able to be used to dilute other additives (e.g. the above-mentioned conventional additives) or melts thereof, so that they can also be sprayed together with these additives onto the polymer to be stabilized. Application by spraying during the deactivation of the polymerization catalysts is especially advantageous, in which case spraying is conveniently effected with the vapour used for deactivation.

[0333] The materials stabilized in that manner may be used in an extremely wide variety of forms, e.g. in the form of films, fibres, tapes, moulding compounds or profiles, or as binders for surface-coatings, especially powder coatings, adhesives or cements.

[0334] The polyolefins stabilized in that manner may likewise be used in an extremely wide variety of forms, especially in the form of thick-layer polyolefin moulded articles that are in lasting contact with extracting media, such as, for example, pipes for liquids or gases, films, fibres, geomembranes, tapes, profiles or tanks.

[0335] The preferred thick-layer polyolefin moulded articles have a layer thickness of from 1 to 50 mm, especially from 1 to 30 mm, e.g. from 2 to 10 mm.

[0336] A preferred embodiment of this invention is therefore the use of compounds of the formula I for stabilizing organic materials against oxidative, thermal or, light-induced degradation.

[0337] The invention also relates to a process for stabilizing an organic material against oxidative, thermal or light-induced degradation, which comprises incorporating therein or applying thereto at least one compound of the formula I.

[0338] The invention relates also to compositions comprising a functional fluid, preferably from the series of lubricants, hydraulic fluids and metal-working fluids and also fuels for powering engines of the 4-stroke, Otto, 2-stroke, diesel, Wankel and orbital types, and at least one compound of the formula I.

[0339] The compounds of the formula I may preferably be used in lubricants and fuels as multifunctional stabilizers, that is to say they combine in themselves antioxidative, friction-reducing, extreme-pressure-protection and wear-protection action and also anti-corrosion properties.

[0340] Preferred lubricants and fuels and related products are engine oils, turbine oils, gear oils, hydraulic fluids, diesel or Otto fuels, metal-working fluids and lubricating greases.

[0341] Especially preferred lubricants are mineral oils, synthetic oils or mixtures thereof.

[0342] Products known per se are used as functional fluids from the series of lubricants, hydraulic fluids and metal-working fluids.

[0343] The lubricants and hydraulic fluids that come into consideration will be familiar to the person skilled in the art and are described in the relevant specialist literature, such as, for example, in Dieter Klamann, “Schmierstoffe und verwandte Produkte” [Lubricants and related products] (Verlag Chemie, Weinheim, 1982), in Schewe-Kobek, “Das Schmiermittel-Taschenbuch” [The lubricant handbook] (Dr. Alfred Hüthig-Verlag, Heidelberg, 1974) and in “Ullmanns Enzyklopädie der technischen Chemie” [Ullmann's Encyclopaedia of Industrial Chemistry], Vol. 13, pages 85-94 (Verlag Chemie, Weinheim, 1977).

[0344] The lubricants are especially oils and greases, for example based on a mineral oil. Oils are preferred.

[0345] A further group of lubricants that may be used are vegetable or animal oils, greases, tallows and waxes or mixtures thereof with one another or mixtures with the mentioned mineral or synthetic oils.

[0346] Vegetable and animal oils, greases, tallows and waxes are, for example, palm-kernel oil, palm oil, olive oil, rapeseed oil, rape oil, linseed oil, groundnut oil, soybean oil, cottonseed oil, sunflower oil, pumpkin seed oil, coconut oil, maize oil, castor oil, tree nut oil and mixtures thereof, fish oils, tallows obtained from slaughtered animals, such as beef tallow, neatsfoot oil and bone oil, and modified, epoxidised and sulfoxidised forms thereof, for example epoxidised soybean oil.

[0347] The mineral oils are based especially on hydrocarbon compounds.

[0348] Examples of synthetic lubricants include lubricants based on aliphatic or aromatic carboxy esters, polymeric esters, polyalkylene oxides, phosphoric acid esters, poly-alpha-olefins or silicones, a diester of a divalent acid with a monohydric alcohol, such as, for example, dioctyl sebacate or dinonyl adipate, a triester of trimethylolpropane with a monovalent acid or with a mixture of such acids, such as, for example, trimethylolpropane tripelargonate, trimethylolpropane tricaprylate or mixtures thereof, a tetraester of pentaerythritol with a monovalent acid or with a mixture of such acids, such as, for example, pentaerythritol tetracaprylate, or a complex ester of monovalent and divalent acids with polyhydric alcohols, for example a complex ester of trimethylolpropane with caprylic and sebacic acid, or a mixture thereof. Apart from mineral oils there are especially suitable, for example, poly-alpha-olefins, ester-based lubricants, phosphates, glycols, polyglycols and polyalkylene glycols, and also mixtures thereof with water.

[0349] Metal-working fluids and hydraulic fluids may be prepared on the basis of the same substances as those described above for the lubricants, such fluids frequently being emulsions of such substances in water or other liquids.

[0350] Lubricant and fuel compositions according to the invention are used, for example, in internal combustion engines, e.g. in motorised vehicles equipped with, for example, engines of the Otto, diesel, two-stroke, Wankel or orbital type.

[0351] The compounds of the formula I are readily soluble in lubricants and fuels, metal-working fluids and hydraulic fluids and are therefore especially suitable as additives for lubricants and fuels, metal-working fluids and hydraulic fluids.

[0352] As additives in lubricants, the compounds of the formula I are effective even in very small amounts. They are mixed in with the lubricants advantageously in an amount of from 0.01 to 5% by weight, preferably in an amount of from 0.05 to 3% by weight and very especially in an amount of from 0.1 to 2% by weight, in each case based on the lubricant.

[0353] The compounds of the formula I may be mixed in with the lubricants and fuels in a manner known per se. The compounds of the formula I are readily soluble, for example, in oils. It is also possible to prepare a so-called master batch, which may be diluted, as a function of use, with the appropriate lubricant or fuel to the concentrations suitable for use. In such cases concentrations above 1% by weight are possible.

[0354] The lubricants and fuels, metal-working fluids and hydraulic fluids may additionally comprise other additives that are added in order to improve their basic properties still further; such additives include: further antioxidants, metal passivators, rust inhibitors, viscosity index improvers, pour-point depressants, dispersants, detergents, coefficient of friction reducers, further extreme-pressure additives and anti-wear additives. Such further additives are added advantageously in an amount of from 0.01 to 5% by weight.

[0355] A number of such compounds can be found, for example, in the above list “1. Antioxidants”, especially points 1.1 to 1.19. In addition, further additives may be mentioned by way of example:

[0356] Examples of Further Antioxidants

[0357] Aliphatic or aromatic phosphites, esters of thiodipropionic acid or thiodiacetic acid or salts of dithiocarbamic or dithiophosphoric acid, 2,2,12,12-tetramethyl-5,9-dihydroxy-3,7,11-trithiatridecane and 2,2,15,15-tetramethyl-5,12-dihydroxy-3,7,10,14-tetrathiahexadecane.

Examples of Metal Deactivators. e.g. for Copper, are

[0358] a) Benzotriazoles and derivatives thereof, e.g. 2-mercaptobenzotriazole, 2,5-dimercaptobenzotriazole, 4- or 5-alkylbenzotriazoles (e.g. tolutriazole) and derivatives thereof, 4,5,6,7-tetrahydrobenzotriazole, 5,5′-methylenebis-benzotriazole; Mannich bases of benzotriazole or tolutriazole, such as 1-[di(2-ethylhexyl)aminomethyl]tolutriazole and 1-[di(2-ethylhexyl)aminomethyl]benzotriazole; alkoxyalkylbenzotriazoles, such as 1-(nonyloxymethyl)benzotriazole, 1-(1-butoxyethyl)benzotriazole and 1-(1-cyclohexyloxybutyl)tolutriazole.

[0359] b) 1,2,4-Triazoles and derivatives thereof, e.g. 3-alkyl- (or -aryl-)1,2,4-triazoles, Mannich bases of 1,2,4-triazoles, such as 1-[di(2-ethylhexyl)aminomethyl]-1,2,4-triazole; alkoxyalkyl-1,2,4-triazoles, such as 1-(1-butoxyethyl)-1,2,4-triazole; acylated 3-amino-1,2,4-triazoles.

[0360] c) Imidazole derivatives, e.g. 4,4′-methylenebis(2-undecyl-5-methyl)imidazole and bis[(N-methyl)imidazol-2-yl]carbinol-octyl ether.

[0361] d) Sulfur-containing heterocyclic compounds, e.g. 2-mercaptobenzothiazole, 2,5-dimercapto-1,3,4-thiadiazole, 2,5-dimercaptobenzothiadiazole and derivatives thereof; 3,5-bis-[di(2-ethylhexyl)aminomethyl]-1,3,4-thiadiazolin-2-one.

[0362] e) Amino compounds, e.g. salicylidene-propylenediamine, salicylaminoguanidine and salts thereof.

Examples of Rust Inhibitors are

[0363] a) Organic acids, their esters, metal salts, amine salts and anhydrides, e.g. alkyl- and alkenyl-succinic acids and their partial esters with alcohols, diols or hydroxycarboxylic acids, partial amides of alkyl- and alkenyl-succinic acids, 4-nonylphenoxyacetic acid, alkoxy- and alkoxyethoxy-carboxylic acids, such as dodecyloxyacetic acid, dodecyloxy(ethoxy)acetic acid and amine salts thereof, and also N-oleoyl-sarcosine, sorbitan monooleate, lead naphthenate, alkenylsuccinic acid anhydrides, e.g. dodecenylsuccinic acid anhydride, 2-(2-carboxyethyl)-1-dodecyl-3-methylglycerol and salts thereof, especially sodium and triethanolamine salts thereof.

[0364] b) Nitrogen-containing compounds, e.g.:

[0365] i. Primary, secondary or tertiary, aliphatic or cycloaliphatic amines and amine salts of organic and inorganic acids, e.g. oil-soluble alkylammonium carboxylates, and 1-[N,N-bis(2-hydroxyethyl)amino]-3-(4-nonylphenoxy)propan-2-ol.

[0366] ii. Heterocyclic compounds, e.g.: substituted imidazolines and oxazolines, e.g. 2-heptadecenyl-1-(2-hydroxyethyl)-imidazoline.

[0367] c) Phosphorus-containing compounds, e.g.:

[0368] Amine salts of phosphoric acid partial esters or phosphonic acid partial esters, zinc dialkyldithiophosphates.

[0369] d) Sulfur-containing compounds, e.g.:

[0370] Barium dinonyinaphthalene sulfonates, calcium petroleum sulfonates, alkylthio-substituted aliphatic carboxylic acids, esters of aliphatic 2-sulfocarboxylic acids and salts thereof.

[0371] e) Glycerol derivatives, e.g.:

[0372] Glycerol monooleate, 1-(alkylphenoxy)-3-(2-hydroxyethyl)glycerols, 1-(alkylphenoxy)-3-(2,3-dihydroxypropyl)glycerols, 2-carboxyalkyl-1,3-dialkylglycerols.

Examples of Viscosity Index Improvers are

[0373] Polyacrylates, polymethacrylates, vinylpyrrolidone/methacrylate copolymers, polyvinylpyrrolidones, polybutenes, olefin copolymers, styrene/acrylate copolymers, polyethers.

Examples of Pour-point Depressants are

[0374] Poly(meth)acrylates, ethylene/vinyl acetate copolymer, alkylpolystyrenes, fumarate copolymers, alkylated naphthalene derivatives.

Examples of Dispersants/Surfactants are

[0375] Polybutenylsuccinic acid amides or imides, polybutenylphosphonic acid derivatives, basic magnesium, calcium and barium sulfonates and phenolates.

Examples of Extreme-pressure and Anti-wear Additives are

[0376] Sulfur- and/or phosphorus- and/or halogen-containing compounds, such as, for example, chlorinated paraffins, sulfurated olefins or vegetable oils (soybean/rape oil), alkyl- or aryl-di- or -tri-sulfides, zinc dialkyldithiophosphates, zinc dithiocarbamates such as zinc diamyldithiocarbamate, molybdenum dithioates such as molybdenum dithiocarbamates, triaryl phosphates such as tritolyl phosphate, tricresyl phosphate, phenyl phosphate isopropyl ester, amine salts of mono- or di-alkylphosphoric acids such as the amine salts of mono-/di-hexyl phosphate, amine salts of alkylphosphonic acids such as the amine salt of methylphosphonic acid, triaryl phosphites such as tris[nonylphenyl] phosphite, dialkyl phosphites such as dioctyl phosphite, triaryl monothiophosphates such as triphenyl thionophosphate or tris[isononylphenyl] thionophosphate or tert-butylated triphenyl thionophosphate, substituted trialkyl mono- or di-thiophosphates such as diisopropoxyphosphinothioyl)thio]propionate or butylene-1,3-bis[(diisobutoxyphosphinothioyl)propionate, trithiophosphates such as trithiophosphoric acid S,S,S-tris(isooctyl-2-acetates), amine salts of 3-hydroxy-1,3-thiaphosphetane-3-oxide, benzotriazoles or derivatives thereof such as bis(2-ethylhexyl)aminomethyltolutriazole, dithiocarbamates such as methylene-bis-dibutyidithiocarbamate, derivatives of 2-mercaptobenzothiazole such as 1-[N,N-bis(2-ethylhexyl)aminomethyl]-2-mercapto-1H-1,3-benzothiazole, derivatives of 2,5-dimercapto-1,3,4-thiadiazole such as 2,5-bis(tert-nonyidithio)-1,3,4-thiadiazole.

Examples of Coefficient of Friction Reducers are

[0377] Lard oil, oleic acid, tallow, rape oil, sulfurated fats, amines. Further examples are given in EP-A-0 565 487.

Examples of Special Additives for Use in Water/Oil Metal-working Fluids and Hydraulic Fluids are

[0378] Emulsifiers: petroleum sulfonates, amines, such as polyoxyethylated fatty amines, non-ionic surface-active substances;

[0379] buffers: alkanolamines;

[0380] biocides: triazines, thiazolinones, tris-nitromethane, morpholine, sodium pyridenethol;

[0381] speed improvers: calcium and barium sulfonates;

Examples of Fuel Additives

[0382] Fuel additives are described in Kirk-Othmer, Encyclopedia of Chemical Technology, Vol 12, 1994 and in this instance are essentially petrol and diesel additives:

[0383] Petrol: dyes, especially azo dyes;

[0384] Antioxidants: aminic, especially para-phenylenediamines, or phenolic, e.g. 2,6-di-tert-butyl-phenol, as described above;

[0385] Metal deactivators: especially N,N′-disalicylidene-1,2-propane, benzotriazole, EDTA;

[0386] Rust inhibitors: for example carboxylic acids, sulfonates, amines or amine salts;

[0387] Dispersants: e.g. esters, high-molecular-weight amines, Mannich bases, succinimides, borated succinimides;

[0388] Detergents: for example fatty acid amides, nonpolymeric amines, polybutene succinimides, polyether amines, low-molecular-weight amines, sulfonates, salicylic acid derivatives;

[0389] Demulsifiers: for example long-chain alcohols or phenols containing poly-ethylene or -butylene groups;

[0390] Antiknock agents: tetralkyl lead, manganese methylcyclopentadienyltricarbonyl;

[0391] Oxygen compounds: esters of vegetable oils, ethers, alcohols for improving burn behaviour;

[0392] Diesel: ignition improvers (cetane improvers), e.g. alkyl nitrates, ether nitrates, alkyl diglycol nitrates, organic peroxides;

[0393] Stabilizers for, especially, cracked diesel: amines and other N-containing compounds that act as radical traps.

[0394] Especially preferred further additives in lubricants are aminic antioxidants, especially mixtures of mono- and di-alkylated tert-butyl-/tert-octyl-diphenylamines.

[0395] The present invention relates also to the use of the components of the formula I for stabilizing organic materials, especially as additives in lubricants and fuels, hydraulic fluids or metal-working fluids, preferably in hydraulic oils and gear oils. The use according to the invention includes protection of the metal components to be lubricated against mechanical attrition (wear protection) and corrosion protection activity and also antioxidation activity—with respect both to the lubricant and to the metal components.

[0396] The present invention accordingly relates also to a method for improving the properties, during use, of organic materials, especially lubricants and fuels, metal-working fluids and hydraulic fluids, wherein a compound of the formula I is added to those materials.

[0397] The photographic materials according to this invention comprise a support bearing at least one layer of a light-sensitive silver halide emulsion.

[0398] Examples of color photographic materials according to this invention are color negative films, color reversal films, color positive films, color photographic paper, color reversal photographic paper, color-sensitive materials for the dye diffusion transfer process or the silver dye bleach process.

[0399] Of especial interest is a color photographic recording material comprising, on a base, at least one blue-sensitive silver halide emulsion layer containing at least one yellow dye providing compound, at least one green-sensitive silver halide emulsion layer containing at least one magenta dye providing compound, at least one red-sensitive silver halide emulsion layer containing at least one cyan dye providing compound, and customary (non light sensitive) top layer(s) and interlayers separating the light-sensitive layers.

[0400] The layers of the color photographic material can be arranged in various orders as is well known in the art.

[0401] The compounds of the formula I can be contained in any of the layers of the photographic material, i.e. in any of the light sensitive silver halide emulsion layers or in a non light sensitive layer. For use as a Dox scavenger, the compound of the formula I is preferably contained in one or more non light sensitive layers. In this case, the light sensitive layers may contain a lower concentration of a compound of the formula I or none.

[0402] The compounds of the formula I are preferably incorporated in an interlayer, especially a non-photosensitive interlayer, adjacent to the green-sensitive layer containing a magenta coupler. Preferred color photographic materials within this invention are those wherein the magenta coupler is of the pyrazolo-azole type, e.g. as disclosed in U.S. Pat. No. 5,538,840, column 49, line 51, until column 69, line 27, and publications cited therein; this section of U.S. Pat. No. 5,538,840 is hereby incorporated by reference.

[0403] Also preferred is a color photographic material, wherein the silver halide emulsion contains at least 95 mol-% AgCl.

[0404] In general, the compounds of the formula I are contained in the photographic material in an amount from 10 to 1000 mg/m², especially from 30 to 500 mg/m².

[0405] The compounds of formula I can be milled with polymers (e.g. PVS, polyester, polyvinyl alcohol etc.) and placed in a layer thus preventing their migration to adjacent layers. Also, compounds of formula I containing a suitable functional group (e.g. ester, hydroxy) can be reacted with a polymer, e.g. a polyvinyl alcohol or polyester, in order to attach them chemically. This form will reduce their migrating tendency.

[0406] Typical bases for the photographic material include polymeric films and paper (including polymer-coated paper). Details regarding supports and other layers of color photographic recording materials can be found in Research Disclosure, Item 36544, September 1994.

[0407] Essential constituents of the photographic emulsion layers are binders, silver halide particles and color couplers. Details regarding the constituents of the light sensitive layers and other (non light sensitive) layers such as top layers and interlayers separating the silver halide emulsion layers can be found in Research Disclosure, Item 38957, September 1996.

[0408] The invention therefore also pertains to a color photographic material comprising a compound of the formula I, and to the use of a compound of the formula I as an additive in a color photographic material.

[0409] The invention also partains to a process for preventing migration of the oxidized developer in a color photographic material from one color sensitive layer to another by incorporating a compound of the formula I into said material.

[0410] The compounds of the formula I of present invention are of special advantage when incorporated into photographic materials containing magenta couplers of the pyrazolotriazole class.

[0411] Examples for especially suitable yellow, magenta and cyan couplers to be used in combination with compounds of the present invention are as given in U.S. Pat. No. 5,538,840, column 33, line 3, until column 73, line 34, and publications cited therein. These passages are hereby incorporated by reference.

[0412] The compounds of the formula I which can be used in the context of this invention can be incorporated into the color photographic recording material, on their own or together with the color coupler and with or without further additives, by pre-dissolving them in high-boiling organic solvents. Preference is given to the use of solvents which boil at higher than 160° C. Typical examples of these solvents are the esters of phthalic acid, phosphoric acid, citric acid, benzoic acid or of fatty acids, and also alkylamides and phenols.

[0413] Further details on the structure of the color photographic material of the invention, and the components or further additives which can be employed in the novel material, can be found, inter alia, in U.S. Pat. No. 5,538,840, column 27, line 25, to column 33, line 2; and further in U.S. Pat. No. 5,538,840 from column 74, line 18, to column 106, line 16; and in U.S. Pat. No.5,780,625, column 12, line 6, until column 57, line 6, and the publications cited in these 2 references; these passages of U.S. Pat. No. 5,538,840 and U.S. Pat. No. 5,780,625 are hereby incorporated by reference. Other useful information, how compounds of the formula I can be used in photographic material, can be taken from EP-A-0 871 066, page 10, line 10, until page 11, line 32, especially the references cited therein.

[0414] The photographic layers in the material of this invention may also include UV absorbers, which screen out the UV light and therefore protect the dyes, the couplers or other components against photodegradation. Hydroquinone compounds according to this invention may be contained in those layers where UV absorbers are present.

[0415] UV absorbers preferably to be used in the novel material or within the process of present invention include benzotriazoles, 2-hydroxybenzophenones, oxanilides, cyanoacrylates, salicylic esters, acrylonitrile derivatives, thiazolines and 2-hydroxyphenyltriazines.

[0416] GB-A-2,319,523 describes from page 49, line 21, until page 73, line 2, further details of the color photographic material, especially couplers (page 52, line 1, until page 56, line 22), UV absorbers (page 56, line 25, until page 68, line 1) and dark stabilizers (page 68, line 2, until page 73, line 2). Preferred UV absorbers of the 2-hydroxyphenyltriazine class are also described in detail, for example, in U.S. Pat. No. 5,668,200, column 1, line 30, until column 7, line 55, and as specific examples from column 26, line 31, until column 32, last line, and, together with some advantageous UV absorbers of the benzotriazole class, in U.S. Pat. No. 5,300,414, column 2 to column 10, line 54. These sections of U.S. Pat. No. 5,668,200 and U.S. Pat. No. 5,300,414 are hereby incorporated by reference.

[0417] The compounds of formula I may be used in combination with any known Dox scavengers such as hydrazines, hydrazides, hydroquinones of e.g. formula HQ-1 or HQ-2; 6-hydroxychromanes of e.g. formula A-3, or hydroxylamines of e.g; formula A-4

[0418] As silver halide emulsions it is possible to use customary silver chloride, silver bromide or silver iodide emulsions or mixtures thereof, such as silver chlorobromide and silver chloroiodide emulsions, in which the silver halides may have all known crystal forms. The use of silver chloride emulsions is accorded particular importance in the material of this novel process. The preparation of such emulsions and their sensitization are described in Research Disclosure, Item 307105, November 1989.

[0419] The compounds of the formula I may preferably also be used as stabilizers for ethylenically unsaturated resins against premature polymerization or crosslinking of the resins during transport or storage.

[0420] Preferred ethylenically unsaturated resins are for example liquid or resin-like monomers, oligomers, co-oligomers, polymers of co-polymers or mixtures thereof, which possess at least one ethylenically unsaturated bond and which are photo-polymerisable or curable with UV light.

[0421] The following Examples illustrate the invention further. Parts or percentages relate to weight.

EXAMPLE 1 Preparation of 5,7-di-tert-butyl-3-(4-trifluoromethyl-phenyl)-3H-benzofuran-2-one (compound (101), Table 1)

[0422] a) Preparation of 2,4-di-tert-butyl-6-[piperidin-1-yl-(4-trifluoromethyl-phenyl)-methyl]-phenol (compound (201), Table 2).

[0423] 8.29 g (97.33 mmol) of piperidine are added, at room temperature, to a solution of 7.74 g (44.43 mmol) of 4-trifluoromethylbenzaldehyde in 50 ml of toluene. The slightly yellow-colored solution is boiled under reflux for 4 hours; approximately 1 ml of water is separated off using a water separator, and a solution of 8.73 g (42.32 mmol) of 2,4-di-tert-butylphenol in 15 ml of toluene is then added dropwise. The reaction mixture is boiled at reflux for further 17 hours and then cooled to room temperature; the solvent is distilled off using a vacuum rotary evaporator. Crystallisation of the residue from iso-propanol/methanol (1:1) yields 15.04 g (79%) of compound (201) (Table 2), m.p. 150-152° C. Molecular weight C₂₇H₃₆F₃NO (447.59). Analysis, calculated: C 72.45; H 8.11; N 3.13%. Analysis, found: C 72.63; H 8.05; N 3.05%. ¹HNMR (300 MHz, CDCl₃, ppm): 1.12 (s, 9H); 1.39 (s, 9H); 1.56 (m, 4H); 2.28 (bm, 6H); 4.37 (s,1 H); 6.65 (d,1 H); 7.08 (d,1 H); 7.47 (m, 4H).

[0424] Compounds (202), (203) and (204) (Table 2) are obtained in analogy to Example 1a using 3-trifluoromethylbenzaldehyde [for (202)], 2-trifluoromethylbenzaldehyde [for (203)] and 3,5-di-trifluoromethylbenzaldehyde [for (204)] instead of 4-trifluoromethylbenzaldehyde.

[0425] b) Preparation of 5,7-di-tert-butyl-3-(4-trifluoromethyl-phenyl)-3H-benzofuran-2-one (compound (101), Table 1).

[0426] A solution of 12.53 g (28.0 mmol) of compound (201), prepared according to Example 1a, in 150 ml of dry toluene is degassed using argon and then 33.6 mg (0.057 mmol) of dichloro-[1,3-bis(diphenylphosphino)propane]palladium(II) and 4.22 ml (112 mmol) of formic acid are added. The autoclave is flushed with carbon monoxide and sealed, and a carbon monoxide pressure of 6 bar is then applied. The reaction mixture is maintained at 140° C. for 14 hours. After cooling to room temperature, the reaction mixture is poured into water and extracted three times using ethyl acetate. The organic phases are combined, dried over sodium sulfate and concentrated using a vacuum rotary evaporator. Filtration of the residue on silica gel using ethyl acetate and crystallisation of the pure fractions from methanol yields 9.46 g (87%) of compound (101) (Table 1), m.p. 127-128° C. Molecular weight C₂₃H₂₅F₃O₂ (390.45). Analysis, calculated: C 70.75; H 6.45%. Analysis, found: C 70.96; H 6.53%. ¹HNMR (300 MHz, CDCl₃, ppm): 1.23 (S, 9H); 1.37 (s, 9H); 4.83 (s, 1H); 6.97 (m, 1H); 7.31 (m, 3H); 7.57 (d, 2H).

[0427] Compounds (102), (103) and (104) (Table 1) are obtained in analogy to Example 1b using compounds (202), (203) and (204) (Table 2) instead of compound (201).

EXAMPLE 2 Preparation of 5,7-di-tert-butyl-3-(4-fluorophenyl)-3H-benzofuran-2-one (Compound (105), Table 1)

[0428] a) Preparation of 2,4-di-tert-butyl-6-[(4-fluorophenyl)-piperidin-1-yl-methyl]-phenol (compound (205), Table 2).

[0429] 8.29 g (97.33 mmol) of piperidine are added, at room temperature, to a solution of 5.52 g (44.43 mmol) of 4-fluorobenzaldehyde in 50 ml of toluene. The slightly yellow-colored solution is boiled under reflux for 16 hours; approximately 1 ml of water is separated off using a water separator, and a solution of 8.73 g (42.32 mmol) of 2,4-di-tert-butylphenol in 15 ml of toluene is then added dropwise. The reaction mixture is boiled at reflux for further 16 hours and then cooled to room temperature; the solvent is distilled off using a vacuum rotary evaporator. Crystallisation of the residue from iso-propanol/methanol (1:1) yields 15.40 g (91%) of compound (205) (Table 2), m.p. 135-1360C. Molecular weight C₂₆H₃₆FNO (397.58). Analysis, calculated: C 78.55; H 9.13; N 3.52%. Analysis, found: C 78.48; H 9.09; N 3.50%. ¹HNMR (300 MHz, CDCl₃, ppm): 1.12 (s, 9H); 1.37 (s, 9H); 1.57 (m, 4H); 2.28 (bm, 6H); 4.35 (s, 1H); 6.63 (d, 1H); 6.91 (dt, 2H); 7.08 (d, 1H); 7.32 (bm, 4H).

[0430] b) Preparation of 5,7-di-tert-butyl-3-(4-fluorophenyl)-3H-benzofuran-2-one (compound (105), Table 1).

[0431] A solution of 11.13 g (28.0 mmol) of compound (205), prepared according to Example 2a, in 150 ml of dry toluene is degassed using argon and then 33.6 mg (0.057 mmol) of dichloro-[1,3-bis(diphenylphosphino)propanelpalladium(II) and 4.22 ml (112 mmol) of formic acid are added. The autoclave is flushed with carbon monoxide and sealed, and a carbon monoxide pressure of 6 bar is then applied. The reaction mixture is maintained at 140° C. for 14 hours. After cooling to room temperature, the reaction mixture is poured into water and extracted three times using ethyl acetate. The organic phases are combined, dried over sodium sulfate and concentrated using a vacuum rotary evaporator. Filtration of the residue on silica gel using ethyl acetate and crystallisation of the pure fractions from methanol yields 8.53 g (90%) of compound (105) (Table 1), m.p. 146-147° C. Molecular weight C₂₂H₂₅FO₂ (340.44). Analysis, calculated: C 77.62; H 7.40%. Analysis, found: C 77.66; H 7.35%. ¹HNMR (300 MHz, CDCl₃, ppm): 1.22 (s, 9H); 1.36 (s, 9H); 4.74 (s, 1H); 6.99 (m, 3H); 7.16 (m, 2H); 7.26 (d,1H).

EXAMPLE 3 Preparation of 5,7-di-tert-butyl-3-(4-cyanophenyl)-3H-benzofuran-2-one (Compound (106), Table 1)

[0432] a) Preparation of 2,4-di-tert-butyl-6-[(4-cyanophenyl)-piperidin-1-yl-methyl]-phenol (compound (206), Table 2).

[0433] 8.29 g (97.33 mmol) of piperidine are added, at room temperature, to a solution of 5.83 g (44.43 mmol) of 4-cyanobenzaldehyde in 50 ml of toluene. The slightly yellow-colored solution is boiled under reflux for 4 hours; approximately 1 ml of water is separated off using a water separator, and a solution of 8.73 g (42.32 mmol) of 2,4-di-tert-butylphenol in 15 ml of toluene is then added dropwise. The reaction mixture is boiled at reflux for further 6 hours and then cooled to room temperature; the solvent is distilled off using a vacuum rotary evaporator. Crystallisation of the residue from methanol yields 12.95 g (75%) of compound (206) (Table 2), m.p. 165-166° C. Molecular weight C₂₇H36N₂O (404.60). Analysis, calculated: C 80.15; H 8.97; N 6.92%. Analysis, found: C 80.01; H 9.00; N 6.78% ¹HNMR (300 MHz, CDCl₃, ppm): 1.12 (s, 9H); 1.36 (s, 9H); 1.57 (m, 4H); 2.28 (bm, 6H); 4.34 (s, 1H); 6.63 (d, 1H); 7.09 (d, 1H); 7.51 (m, 4H).

[0434] Compounds (207) and (208) (Table 2) are obtained in analogy to Example 3a using 3-cyanobenzaldehyde [for (207)] and 3,5-dicyanobenzaldehyde [for (208)] instead of 4-cyanobenzaldehyde.

[0435] b) Preparation of 5,7-di-tert-butyl-3-(4-cyanophenyl)-3H-benzofuran-2-one (compound (106), Table 1).

[0436] A solution of 11.33 g (28.0 mmol) of compound (206), prepared according to Example 3a, in 150 ml of dry toluene is degassed using argon and then 33.6 mg (0.057 mmol) of dichloro-[1,3-bis(diphenylphosphino)propane]palladium(II) and 4.22 ml (112 mmol) of formic acid are added. The autoclave is flushed with carbon monoxide and sealed, and a carbon monoxide pressure of 6 bar is then applied. The reaction mixture is maintained at 140° C. for 14 hours.

[0437] After cooling to room temperature, the reaction mixture is poured into water and extracted three times using ethyl acetate. The organic phases are combined, dried over sodium sulfate and concentrated using a vacuum rotary evaporator. Filtration of the residue on silica gel using ethyl acetate and crystallisation of the pure fractions from methanol yields 7.72 g (79%) of compound (106) (Table 1), m.p. 136-137° C. Molecular weight C₂₃H₂₅NO₂ (347.46). Analysis, calculated: C 79.51; H 7.25; N 4.03%. Analysis, found: C 79.36; H 6.98; N 3.82%. ¹HNMR (300 MHz, CDCl₃, ppm): 1.23 (s, 9H); 1.36 (s, 9H); 4.83 (s, 1H); 6.95 (m, 1H); 7.31 (m, 3H); 7.61 (d, 2H).

[0438] Compounds (107) and (108) (Table 1) are obtained in analogy to Example 3b using compounds (207) and (208) (Table 2) instead of compound (206).

EXAMPLE 4 Preparation of 5,7-di-tert-butyl-3-(4-methoxycarbonylphenyl)-3H-benzofuran-2-one (Compound (109), Table 1)

[0439] a) Preparation of 2,4-di-tert-butyl-6-[(4-methoxcarbonylphenyl)-piperidin-1-yl-methyl]-phenol (compound (209), Table 2).

[0440] 18.98 g (222.94 mmol) of piperidine are added, at room temperature, to a solution of 16.71 g (101.78 mmol) of 4-methoxycarbonylbenzaldehyde in 100 ml of toluene. The slightly yellow-colored solution is boiled under reflux for 15 hours; approximately 2 ml of water is separated off using a water separator, and a solution of 20.0 g (96.93 mmol) of 2,4-di-tert-butylphenol in 30 ml of toluene is then added dropwise. The reaction mixture is boiled at reflux for 1 hour and then cooled to room temperature; the solvent is distilled off using a vacuum rotary evaporator. Crystallisation of the residue from iso-propanol yields 32.12 g (75%) of compound (209) (Table 2), m.p. 167-168° C. Molecular weight C₂₈H₃₉NO₃ (437.63). Analysis, calculated: C 76.85; H 8.98; N 3.20%. Analysis, found: C 76.68; H 8.84; N 3.01%. ¹HNMR (300 MHz, CDCl₃, ppm): 1.11 (s, 9H); 1.37 (s, 9H); 1.56 (m, 4H); 2.30 (bm, 6H); 3.82 (s, 3H); 4.40 (s, 1H) 6.64 (d, 1H); 7.08 (d, 1H); 7.45 (bd, 2H); 7.90 (dd, 2H).

[0441] b) Preparation of 5,7-di-tert-butyl-3-(4-methoxycarbonylphenyl)-3H-benzofuran-2-one (compound (109), Table 1).

[0442] A solution of 10.50 g (24.0 mmol) of compound (209), prepared according to Example 4a, in 120 ml of dry toluene is degassed using argon and then 28.8 mg (0.048 mmol) of dichloro-[1,3-bis(diphenylphosphino)propane]palladium(II) and 3.62 ml (96 mmol) of formic acid are added. The autoclave is flushed with carbon monoxide and sealed, and a carbon monoxide pressure of 6 bar is then applied. The reaction mixture is maintained at 140° C. for 14 hours. After cooling to room temperature, the reaction mixture is poured into water and extracted three times using ethyl acetate. The organic phases are combined, dried over sodium sulfate and concentrated using a vacuum rotary evaporator. Filtration of the residue on silica gel using ethyl acetate and crystallisation of the pure fractions from methanol yields 7.41 g (81%) of compound (109) (Table 1), m.p. 135-136° C. Molecular weight C₂₄H₂₈O₄ (380.49). Analysis, calculated: C 75.76; H 7.42%. Analysis, found: C 75.67; H 7.28%. ¹HNMR (300 MHz, CDCl₃, ppm): 1.22 (s, 9H); 1.37 (s, 9H); 3.85 (s, 3H); 4.74 (s, 1H); 6.96 (m, 1H); 7.26 (m, 3H); 7.98 (d, 2H).

EXAMPLE 5 Preparation of 5,7-di-tert-butyl-3-(4-n-octyloxycarbonylphenyl)-3H-benzofuran-2-one (Compound (110), Table 1)

[0443] A suspension of 14.0 g (36.80 mmol) of compound (109), prepared according to Example 4b, 23.26 ml (147.2 mmol) of 1-octanol and 92 mg (0.368 mmol) of dibutyltinoxide (Bu₂SnO) is heated at 170° C. for 2 hours, whereas an orange solution is formed. Methanol is continuously distilled off the reaction mixture. After cooling to room temperature, the crude reaction mixture is treated with a 50 ml of a 1:19 mixture of ethyl acetate/hexane 1:1 and filtered through a pad of silica. Removal of the solvent using a vacuum rotary evaporator yields 17.53 g (99%) of compound (110) (Table 1), as a pale yellow oil. ¹HNMR (300 MHz, CDCl₃, ppm): 0.90 (t, 3H); 1.35 (s, 9H); 1.38 (bs, 10H); 1.46 (s, 9H); 1.78 (q, 2H); 4.33 (t, 3H); 4.92 (s, 1H); 7.05 (s, 1H); 7.35 (d, 2H); 7.36 (s, 1H); 8.07 (d, 2H).

[0444] Compounds (111), (112), (113), (114), (115), (116) and (117) (Table 1) are obtained in analogy to Example 5 using 1-dodecanol, 1-octadecanol, 1-nonadecanol, 1-docosanol, 2-ethylhexanol, 1,6-hexanediol and 1,12-dodecanediol instead of 1-octanol. For the preparation of compounds (116) and (117) only half of an equivalent of 1,6-hexanediol and 1,12-dodecanediol in respect to the compound (109) was used. TABLE 1 no. compound 101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

[0445] TABLE 2 no. compound 201

202

203

204

205

206

207

208

209

EXAMPLE 6 Prevention of Migration of the Oxidized Developer in a Color Photographic Material

[0446] To evaluate compounds of this invention with respect to their ability as interlayer scavengers for oxidized developing agent, three layer photographic test elements are prepared by providing layers in the order indicated on a polyethylene-coated paper support:

[0447] Test element 1 (reference sample)

[0448] (1) A photosensitive layer containing:

[0449] 260 mg.m⁻² (based on silver) of an unsensitized silver bromide emulsion.

[0450] 1875 mg.m⁻² of gelatin.

[0451] 250 mg.m^(—2) of magenta-dye-forming coupler M-2

[0452] 250 mg.m⁻² of tricresylphosphate.

[0453] 2-sulfonate-4,8-diisobutyl-naphtalene, sodium salt surface active agent.

[0454] 7-methyl-5-hydroxy-1,3,8-triazaindolizine antifoggant.

[0455] (2) An interlayer containing:

[0456] 1800 mg.m⁻² of gelatin.

[0457] 300 mg.m⁻² of tricresylphosphate.

[0458] 2-sulfonate-4,8-diisobutyl-naphtalene, sodium salt surface active agent.

[0459] (3) A layer containing:

[0460] 1800 mg.m⁻² of gelatin.

[0461] 180 mg.m⁻² of dibutylphthalate.

[0462] 2-sulfonate-4,8-diisobutyl-naphtalene, sodium salt surface active agent.

[0463] 2-hydroxy-4,6-dichloro-1,3,5-triazine, potassium salt hardener.

[0464] Test element 2 (control sample)

[0465] (1) A photosensitive layer having the same composition as the photosensitive layer of test element 1.

[0466] (2) An interlayer having the same composition as the interlayer of test element 1.

[0467] (3) A layer containing:

[0468] 1800 mg.m⁻² of gelatin.

[0469] 272 mg.m⁻² of cyan-dye-forming coupler C-2

[0470] 180 mg.m⁻² of dibutylphthalate.

[0471] 2-sulfonate-4,8-diisobutyl-naphtalene, sodium salt surface active agent.

[0472] 2-hydroxy-4,6-dichloro-1,3,5-triazine, potassium salt hardener.

[0473] Test elements 3 and 4

[0474] (1) A photosensitive layer having the same composition as the photosensitive layer of test element 1.

[0475] (2) An interlayer containing:

[0476] 1800 mg.m⁻² of gelatin.

[0477] 20 mg.m⁻² of oxidized developer scavenger as indicated in Table 3 below

[0478] 300 mg.m⁻² of tricresylphosphate.

[0479] 2-sulfonate-4,8-diisobutyl-naphtalene, sodium salt surface active agent.

[0480] (3) A layer having the same composition as the top layer of test element 2.

[0481] The test elements are imagewise exposed through a step wedge with density increment 0.15 and thereafter subjected to the AGFA P-94 developing process.

[0482] Upon processing of the test elements, some oxidized developer is prone to migrate from the layer in which it is formed, for example the undermost, magenta-dye-providing layer, to the topmost layer containing the cyan-dye-forming coupler, thereby producing unwanted cyan dye. The amount of cyan dye that is generated depends on the ability of the interlayer to prevent the diffusion of oxidized developer. The cyan density at the exposure amount giving a magenta density of 1.5 is reported in Table 3. Any cyan density inferior to that observed for test element 2 indicates scavenging of the oxidized developer. TABLE 3 Cyan density at a magenta Test element Interlayer scavenger density of 1.5 1 (reference) — 0.239 2 (control) — 0.293 3 Compound (109) 0.254 4 Compound (101) 0.253

[0483] It is clear from the data in Table 3 that compounds within the scope of this invention are quite effective in preventing the oxidized developer from wandering and forming dye in the wrong layer.

EXAMPLE 7 Stabilization of Multiple-extruded Polypropylene

[0484] 1.3 kg of polypropylene powder (Profax 6501), which has been prestabilized with 0.025% of Irganox®1076 (n-octadecyl 3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionate) (melt index 3.2 g/10 min, measured at 230° C./2.16 kg) are blended with 0.05% of Irganox®1010 (pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]), 0.05% of calcium steareate, 0.33% of DHT 4A® (Kyowa Chemical Industry Co., Ltd., [Mg_(4.5)Al₂(OH)₁₃CO₃·3.5H₂O]) and 0.05% of compound of Table 4. This blend is then extruded in an extruder having a cylinder diameter of 20 mm and a length of 400 mm at 100 rpm, the 3 heating zones being adjusted to the following temperatures: 260, 270, 280° C. The extrudate is cooled by drawing it through a water bath and is then granulated. This granulate is repeatedly extruded. After 3 extrusions, the melt index is measured (at 230° C./2.16 kg). A substantial increase in the melt index denotes pronounced chain degradation, i.e. poor stabilization. The results are summarized in Table 4. TABLE 4 Compound of Melt index after 3 Table 1 extrusions — 17.5 101 4.7 105 4.7 106 4.7 109 4.8 110 4.7

EXAMPLE 8 Stabilization of Polyethylene During Processing

[0485] 100 parts of polyethylene powder (Lupolene®5260 Z) are blended with 0.05 part of Irganox®1010 (pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]) and 0.05 part of a compound of Table 5 and the blend is kneaded in a Brabender plastograph at 220° C. and 50 rpm. During this time the kneading resistance is recorded continuously as torque. In the course of the kneading time the polymer begins to crosslink after prolonged constancy, as can be determined by the rapid increase in torque. The time taken until a marked increase in torque is shown in Table 5 as a measure of the stabilizing action. The longer this time is the better the stabilizing action. TABLE 5 Compound of Time until increase Table 1 in torque (min) — 9.7 101 27.5 105 27.0 106 27.5 109 27.5 110 27.5

EXAMPLE 9 Stabilization of Multiple-extruded Polypropylene at High Temperature

[0486] 1.5 kg of polypropylene powder (Profax 6501), which has been prestabilized with 0.008% of Irganox®1076 (n-octadecyl 3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionate) (melt index 3.2 g/10 min, measured at 230° C./2.16 kg) are blended with 0.05% of Irganox®1010 (pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]), 0.10% of calcium stearate and 0.015 to 0.100% of stabilizer or stabilizer mixture according to Table 6. This blend is then extruded in an extruder having a cylinder diameter of 20 mm and a length of 400 mm at 100 rpm, the 3 heating zones being adjusted to the following temperatures: 280, 320, 340° C. The extrudate is cooled by drawing it through a water bath and is then granulated. This granulate is repeatedly extruded. After 5 extrusions, the melt index is measured (at 230° C./2.16 kg). A substantial increase in the melt index denotes pronounced chain degradation, i.e. poor stabilization. The results are summarized in Table 6. TABLE 6 Melt index after 5 Concentration in extrusions Stabilizers % (by weight) 280° C. 320° C. 340° C. Irgafos ® 168^(a)) 0.100 9.7 43.8 80.1 Sandostab ® P-EPQ^(b)) 0.050 6.3 23.9 61.5 Compound (101) 0.015 8.5 19.6 22.5 Irgafos ® 168^(a)) 0.045 7.2 24.2 26.5 Compound (101) 0.005 Sandostab ® P-EPQ^(b)) 0.045 5.7 15.9 24.7 Compound (101) 0.005

[0487] For footnotes a) and b) see the end of Table 25.

EXAMPLE 10 Preparation of Polyether/Polyurethane Soft Foams as Well as the Stabilization Thereof

[0488] Exactly 470 mg (0.3%, based on the polyol) of a stabilizer mixture of this invention is dissolved in 157 g of an antioxidant-free polyether/polyol, Lupranola2045 (trifunctional polyether/polyol having primary hydroxyl groups; hydroxyl number 35 mg KOH/g, water content less than 0.1%, acid number less than 0.1 mg KOH/g). 10.24 g of a solution consisting of 1.74 g Tecostab® (polysilicone supplied by Goldschmidt, Germany], 0.48 g diazabicyclooctane (amine catalyst) and 0.8 g of water are added and the reaction mixture is stirred vigorously for 60 seconds at 100 rpm. 3.2 g of a solution of 0.32 g of tin octoate (catalyst) in 2.9 g of the above polyol is added and the reaction mixture is again stirred vigorously for 60 seconds at 100 rpm. With vigorous stirring, 98 g of an isocyanate (Lupranat®T80, supplied by BASF; toluylene-2,4- and toluylene-2,6-diisocyanate mixture) are then added immediately and after 6 seconds the mixture is poured into a lined mould and the exothermic temperature is measured during foaming to a foam block. The foam blocks are cooled for 24 hours in a climatic chamber at 5° C. and stored. 2 cm slices are sawed from the center of the blocks and round (cylindrical) test samples are cut therefrom using a boring tool. The samples are aged in a test tube in the presence of air at room temperature and 200° C. for 30 minutes in a preheated alu-block thermostat (dynamic heat test). The yellowing of these test samples is determined as Yellowness Index (YI) according to ASTM D-1925-77. Low YI values denote little discoloration, high YI values severe discoloration of the samples. The results are summarized in Tables 7 and 8. TABLE 7 Concentration of stabilizers YI YI Example in % (by weight) room temp. 200° C. 10a^(i)) — 1.0 70.0 10b^(k)) 0.15% Compound (101) −1.1 2.0 0.15% Irganox ® 5057^(c)) 10c^(k)) 0.15% Compound (102) −0.9 1.8 0.15% Irganox ® 5057^(c)) 10d^(k)) 0.15% Compound (104) −1.3 2.0 0.15% Irganox ® 5057^(c))

[0489] TABLE 8 Concentration of stabilizers YI YI Example in % (by weight) room temp. 200° C. 10e^(i)) — 0.5 69.0 10f^(k)) 0.10% Compound (101) −1.1 2.1 0.10% Irganox ® 5057^(c)) 0.10% Irganox ® 1135^(d)) 10g^(k)) 0.10% Compound (102) −0.9 1.9 0.10% Irganox ® 5057^(c)) 0.10% Irganox ® 1135^(d)) 10h^(k)) 0.10% Compound (104) −1.3 2.0 0.10% Irganox ® 5057^(c)) 0.10% Irganox ® 1135^(d))

[0490] For footnotes c), d), i) and k) see the end of Table 25.

EXAMPLE 11 Stabilizing Polypropylene Fibers Processed at 300° C.

[0491] 2.0 kg of polypropylene powder (B 10 FB® from Polychim S.A., France), which has a melt index of 12.0 g/dmin measured in accordance with DIN 53735 at 230° C. under 2.16 kg, is homogenized with 0.05% of calcium stearate and with the stabilizers indicated in Tables 9 and 10 for 2 minutes in a high-speed mixer. This mixture is extruded at 60 revolutions per minute in an extruder having a barrel diameter of 20 mm and a length of 400 mm, the three heating zones being set at the following temperatures: 200, 220 and 220° C. The extrudate is passed through a water bath for cooling and then granulated. These granules are processed to give a multifilament fiber. This is done using a single-screw extruder with a melt pump and a 37-hole spinning head. The maximum processing temperature is 300° C.

[0492] A portion of the unstretched fiber thus obtained is pressed for 6 minutes at 230° C. to form a sheet with a thickness of 2 mm. The melt index (MFI, melt flow index) of this sheet is measured in accordance with DIN 53735 at 230° C. and 2.16 kg. A large increase in the melt index denotes severe chain degradation and thus poor stabilization. The results are compiled in Table 9.

[0493] Another portion of the unstretched fiber thus obtained is treated with a lubricant (Limanol®P 25, Schill und Seilacher, Boblingen, Germany) and subjected to preliminary drawing. This preliminary drawing leads to a fiber strand having a linear density of 416 g/90 m. This means that a fiber strand 90 m in length has a weight of 416 g. In a further operation, this fiber strand is again drawn at 120° C. by a factor of 3.2 using a drawing apparatus. This leads to a fiber strand having a linear density of 130 g/90 m.

[0494] A portion of this fiber strand is used to produce a knitted tube. The yellowness index (YI₁) of this knitted tube is determined in accordance with ASTM D 1925-77. Low YI₁ values denote little discoloration, high YI₁ values severe discoloration of the samples. The results are compiled in Table 9. This knitted tube is exposed in the presence of from 4 to 6 ppm nitrogen dioxide (NO2) at 40° C. and 87% relative atmospheric humidity for 48 hours in accordance with AATCC 164. The yellowness index (YI₂) of this exposed knitted tube is determined in accordance with ASTM D 1925-77. Low YI₂ values denote little discoloration, high YI₂ values severe discoloration of the samples. The results are compiled in Table 9.

[0495] Another portion of the fiber strand is used to carry out an oven ageing test at 100° C. In this test, a measurement is made, in days, of the time taken for the fiber strand to tear under the test conditions. The longer the period before tearing of the fiber strand, the better the stabilization. The results are compiled in Table 10.

[0496] Another portion of the unstretched fiber is pressed for 6 minutes at 230° C. to form a thin film with a thickness of 0.10 mm. This film is subjected to a Xenon test in accordance with DIN 53387. In this test, the film is exposed in a Xenon 1200 weathering apparatus until a carbonyl index of 0.25 is observed in the wavelength range from 1760 to 1680 cm⁻¹. The larger the number, the better the stabilization. The results are compiled in Table 10. TABLE 9 YI₁ after YI₂ after MFI Example Stabilizers spinning NO₂ exposure after spinning 11a^(i)) — 0.3 1.2 110.0 11b^(k)) 0.100% Compound (106) 1.3 4.5 34.3 0.050% Tinuvin ® 622^(e)) 11c^(k)) 0.100% Compound (106) 1.5 5.3 32.5 0.050% Chimassorb ® 944^(f)) 11d^(k)) 0.100% Compound (106) 0.6 4.2 31.8 0.050% Chimassorb ® 119^(g)) 11e^(k)) 0.075% Compound (106) 0.6 4.6 32.3 0.050% Tinuvin ® 622^(e)) 0.075% Irgafos ® 168^(a)) 11f^(k)) 0.075% Compound (106) 1.4 5.9 33.5 0.050% Chimassorb ® 944^(f)) 0.075% Irgafos ® 168^(a)) 11g^(k)) 0.075% Compound (106) 1.6 4.6 31.6 0.050% Chimassorb ® 944^(f)) 0.075% Irgafos ® 38^(h)) 11h^(k)) 0.075% Compound (106) 1.5 4.7 32.5 0.050% Chimassorb ® 119^(g)) 0.075% Irgafos ® 168^(a))

[0497] For footnotes a), e), f), g), h), i) and k) see the end of Table 25. TABLE 10 Oven ageing Xenon test Example Stabilizers (days) (hours) 11a^(i)) — 1 195 11c^(k)) 0.100% Compound (106) 38 1345 0.050% Chimassorb ® 944^(f)) 11d^(k)) 0.100% Compound (106) 37 1580 0.050% Chimassorb ® 119^(g)) 11f^(k)) 0.075% Compound (106) 39 1320 0.050% Chimassorb ® 944^(f)) 0.075% Irgafos ® 168^(a)) 11g^(k)) 0.075% Compound (106) 39 1325 0.050% Chimassorb ® 944^(f)) 0.075% Irgafos ® 38^(h)) 11h^(k)) 0.075% Compound (106) 38 1610 0.050% Chimassorb ® 119^(g)) 0.075% Irgafos ® 168^(a))

[0498] For footnotes a), f), g), h), i) and k) see the end of Table 25.

EXAMPLE 12 Preparation of Polyolefin Hollow Articles by the Rotomolding Process

[0499] 100 Parts of low density polyethylene, copolymerized with hexene (PE-LLD), type Quantum® Petrothene® GA-635-661, having a melt flow index of 6.5 g/10 min and a density of 0.935 g/cm³, are mixed with 0.170 part of Chimassorb® 944 [formula see footnote (b) after Table 10], 0.050 part of zinc stearate and the stabilizers cited in Tables 11 and 12 at 232° C. in a Superior/MPM Extruder, fitted with a 24:1 Maddock type UD screw, at 100 revolutions per minute. The polymer is then ground. The particle size of the polymer is from 150 to 500 μm. Owing to the larger surface of the particles obtained by grinding, the heat can be absorbed faster, which goes hand in hand with a lower energy consumption.

[0500] The actual rotomolding process or rotational molding process, which permits the production of fairly large three-dimensional solids, is carried out in a Clamshell type rotomolder FSP M20. In this machine, an aluminium mold, which is mounted on an arm and into which the plastic sample is filled, is heated with a gas burner with circulation of the hot air over 5 minutes to 316° C., or over 6 minutes to 329° C., and is then kept at this temperature for a specific time (see Tables 11 and 12). Subsequently, the oven is opened and the mold is cooled first for 7 minutes with circulating air, then for 7 minutes by spraying with water and finally for another 2 minutes with circulating air. During the entire heating and cooling process, the mold, which is mounted on two axes at right angles to each other, is rotated, the speed of the main axis being kept at 6 revolutions per minute and the rotational ratio being 4.5:1. After cooling, the lid of the mold is opened and the resultant hollow article is taken out. The yellowness index (YI) of the exterior of the molded articles is determined according to ASTM D 1925-70. Low YI values denote little discoloration, high YI values strong discoloration of the samples. The less discoloration, the more effective the stabilizer. The results are summarized in Tables 11 and 12. TABLE 11 Rotomolding at 316° C. Yellowness Index after Examples Stabilizer 8 minutes 10 minutes Example 12a^(i)) 0.05% Irganox ® 1010^(l)) 6.2 17.7 0.10% Irgafos ® 168^(a)) Example 12b^(k)) 0.02% compound (107) 4.2 5.2 0.08% Irgafos ® 168^(a))

[0501] TABLE 12 Rotomolding at 329° C. Yellowness Index after Examples Stabilizer 6 minutes 8 minutes Example 12c^(i)) 0.05% Irganox ® 1010^(l)) 3.9 16.5 0.10% Irgafos ® 168^(a)) Example 12d^(k)) 0.02% compound (107) 4.1 5.6 0.08% Irgafos ® 168^(a))

[0502] For footnotes a), i), k) and l) see the end of Table 25.

EXAMPLE 13 Stabilisation of Polyethylene Which is in Permanent Contact With Water

[0503] 0.10% by weight of calcium stearate and a stabilizer mixture comprising 0.10% by weight of Irganox®1010 (pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]), 0.05% by weight of Irgafos®168 (tris(2,4-di-tert-butylphenyl)phosphite) and 0.05% by weight of compound (104) (Table 1) is added dry to a polyethylene polymer (Hostalene® CRP 100; PE-HD) taken direct from a reactor and are incorporated therein in a Pappenmaier mixer (type 20) within 2 minutes.

[0504] In an extruder, of Schwabenthan, the stabilized polyethylene is homogenised and processed to granulate. For the extraction tests in water, 200 mm by 150 mm by 2 mm test plates are pressed from the granulate of the individual formulations using a table press. To ease the demoulding of the test plates, the pressing process is carried out between two aluminium foils.

[0505] The stabilizer extraction tests are carried out with deionised water. Preliminary heating of the extraction vessels is carried out in a circulating air oven, of Heraeus (Hanau, Germany), at a maximum temperature deviation of 1.5° C. Glass vessels are used for extraction tests below the boiling point of water, such as at 80° C. Owing to the risk of oversaturating the water with stabilizers, the amount of liquid used for the tests is fixed at c. 400 ml per c. 70 g of polymer and the water is replaced with fresh water at regular intervals, i.e. whenever a sample is taken.

[0506] The test plates are subjected to the above test conditions for 50 days at 80° C. Upon termination of the extraction test, the residual stabilizer content and the oxidation induction time of the test plates are determined.

[0507] The residual content of sterically hindered phenol, Irganox®1010, is determined using an internal standard in an HPLC appliance of the Spectra Physics SP 8800 type, equipped with autosampler and UVNIS detector of the Spectra 200 type. The chromatography is carried out at room temperature using a Hyperchrome 125×4.6 mm type column which is filled with Nucleosil C 185 μm. The injection volume is 14 μl at a flow rate of 1.5ml/minute. UV detection takes place at 270 nm.

[0508] The oxidation induction time which is determined using a “DuPont-Instrument 910 Differential Scanning Calorimeter”, of TA Instruments (Alzenau, Germany), and taking a 5 to 10 mg amount of sample, describes the time in minutes at constant thermal stress (190° C./O₂) up to the start of the complete degradation of the polyethylene sample. The longer the oxidation induction time, the better stabilized the polyethylene and the more stable is the polyethylene against extracting water with which it is in permanent contact. The results show that the stability of polyolefins which are in permanent contact with extracting media is improved if they contain a compound of the formula I according to the instant invention as stabilizer.

EXAMPLE 14 Measuring the Discoloration of Powder Coatings Based on a Carboxy-functional Polyester and Cured in Electric and Gas Ovens

[0509] To prepare the powder coating composition based on a carboxy-functional polyester, components 1 to 6 (formulation without additives) or components 1 to 7 (formulation containing the stabilizers) are employed in the sequence indicated (cf. Table 13). TABLE 13 Examples (amount in grams) Components 1a 1b to 1i 1. Crylcoat ® 360^(a)) 591 591 2. Araldit ® GT 7004^(b)) 394 394 3. Octadecyltrimethylammonium bromide^(c)) 3.6 3.6 4. Resiflow ® PV 88^(d)) 12 12 5. Benzoin^(e)) 3 3 6. Titanium dioxide type R-KB-5^(f)) 500 500 7. Stabilizers (see Tables 14 and 15) — 6 Total: 1503.6 1509.6

[0510] The components weighed out in this way are mixed using a planetary stirrer. The mixture is then extruded on a prism extruder at 300 revolutions/minute and at 100° C. and is rolled out.

[0511] The powder coating composition is coarsely comminuted using a bench cutter and is ground in a Retsch ZM-1 ultracentrifugal mill with a 0.75 mm annular-perforation screen at 15,000 revolutions/minute. Finally, the powder is passed through a 30 μm screen on a centrifugal screening machine.

[0512] The finished powder coating composition is sprayed electrostatically to a coat thickness of 70 μm onto aluminium panels using an ESB-Wagner corona cup gun at 60 kV. Some of the coated panels are cured at 180° C. for 90 minutes in an electric oven. The remaining coated panels are cured at 180° C. for 45 minutes in a gas oven with an NO₂ content of 20 ppm. The yellowness index (YI) of the samples is determined in accordance with ASTM D 1925-70. Low YI values denote little discoloration, high YI values denote severe discoloration of the samples. The less the discoloration, the more effective the stabilizer. The results are summarized in Tables 14 and 15. TABLE 14 Curing for 90 minutes in an electric oven at 180° C. Yellowness index Stabilizers after 90 minutes Examples (% rel. to components 1 to 5) (ASTM D 1925-70) Example 14a^(i)) — 3.1 Example 14b^(k)) 0.60% Compound (110) 2.7 Example 14c^(k)) 0.50% Irgafos ® 168^(a)) 2.7 0.10% Compound (110) Example 14d^(k)) 0.15% Irgafos ® 168^(a)) 2.7 0.15% HALS mixture^(m)) 0.30% Compound (110) Example 14e^(k)) 0.15% Irgafos ® 168^(a)) 2.7 0.15% Irganox ® 1010^(l)) 0.30% Compound (110)

[0513] For footnotes a), i), k), m) and l) see the end of Table 25. TABLE 15 Curing for 45 minutes in a gas oven at 180° C. Yellowness index Stabilizers after 90 minutes Examples (% rel. to components 1 to 5) (ASTM D 1925-70) Example 14f^(i)) — 4.2 Example 14g^(k)) 0.60% Compound (110) 3.4 Example 14h^(k)) 0.50% Irgafos ® 168^(a)) 3.4 0.10% Compound (110) Exapmle 14i^(k)) 0.15% Irgafos ® 168^(a)) 3.2 0.15% HALS mixture^(m)) 0.30% Compound (110)

[0514] For footnotes a), i), k) and m) see the end of Table 25.

EXAMPLE 15 Stabilizing Polypropylene in the Case of Multiple Extrusion and at Especially High Temperatures

[0515] 1.5 kg of polypropylene powder (Profax®6501), which has been initially stabilized with 0.008% of Irganox®1076 (n-octadecyl 3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionate) (with a melt index of 3.2 measured at 230° C. and under 2.16 kg), are mixed with 0.10% of calcium stearate and 0.015 to 0.20% of the stabilizers listed in Table 16. This mixture is extruded in an extruder having a barrel diameter of 20 mm and a length of 400 mm at 100 revolutions per minute, the maximum extruder temperature being set at 280, 300, 320 and 340° C. For cooling, the extrudate is drawn through a water bath and then granulated. These granules are extruded repeatedly. After 5 extrusions, the melt index is measured (at 230° C. under 2.16 kg). A large increase in the melt index denotes severe chain breakdown and hence poor stabilization. The results are summarized in Table 16. TABLE 16 Amount Melt index after Example Stabilizers (% by wt.) 5 extrusions Example 15a^(i)) Irgafos ® 168^(a)) 0.10 18.2 Irganox ® 1010^(l)) 0.10 Chimassorb ® 944^(f)) 0.20 Example 15b^(k)) Compound (101) 0.015 8.7 Irgafos ® 168^(a)) 0.10 Irganox ® 1010^(l)) 0.05 Chimassorb ® 944^(f)) 0.10 Example 15c^(k)) Compound (101) 0.015 8.3 Irgafos ® 168^(a)) 0.10 Irganox ® 1010^(l)) 0.05 Chimassorb ® 119^(g)) 0.10

[0516] For footnotes a), f), g), i), k) and l) see the end of Table 25.

EXAMPLE 16 Stabilization of Polycarbonate

[0517] 1.0 kg of a polycarbonate powder which has been dried for 8 hours at 120° C. in a vacuum drying oven (Lexan®115, of General Electric) and 0.1 to 0.6 g (0.01 to 0.06%) of the stabilizers listed in Table 17 are mixed for 2 minutes in a Henschel mixer. This mixture is then extruded in a Schwabenthan extruder at a maximum of 280° C. The polymer string is then granulated. Using an injection moulding machine, plates having a layer thickness of 2 mm are then moulded from the granulate so obtained at a maximum of 300° C. These plates are then aged in a circulating air oven at 135° C. for 2000 hours. The yellowness index (YI) of these plates is then determined according to ASTM D 1925-70 and the transmission is determined in percent at 450 nm. Low YI values denote little discoloration, high YI values high discoloration of the patterns. The less discoloration, the more effective the stabilizer. The higher the transmission values, the more effective the stabilizer. The results are compiled in Tables 17 and 18. TABLE 17 Yellowness Yellowness index index prior to after 2000 hours Example Stabilizers oven-ageing at 135° C. 16a^(i)) — 4.2 25.0 16b^(i)) 0.05% Irgafos ® 168^(a)) 3.4 23.5 16c^(k)) 0.01% Compound (101) 3.4 16.4 16d^(k)) 0.01% Compound (112) 3.5 14.3 16e^(k)) 0.05% Irgafos ® 168^(a)) 3.2 15.2 0.01% compound (101) 16f^(k)) 0.05% Irgafos ® 168^(a)) 3.1 14.3 0.01% compound (112)

[0518] TABLE 18 Transmission Transmission in % in % prior to after 2000 hours at Example Stabilizers oven-aging 135° C. 16a^(i)) — 84.7 76.4 16b^(i)) 0.05% Irgafos ® 168^(a)) 84.7 77.8 16c^(k)) 0.01% Compound (101) 85.8 81.3 16d^(k)) 0.01% Compound (112) 85.9 81.8 16e^(k)) 0.05% Irgafos ® 168^(a)) 85.7 81.3 0.01% Compound (101) 16f^(k)) 0.05% Irgafos ® 168^(a)) 85.9 81.9 0.01% compound (112)

[0519] For footnotes a), i) and k) see the end of Table 25.

EXAMPLE 17 Stabilization of Polycarbonate

[0520] 1.0 kg of a polycarbonate powder which has been dried for 8 hours at 120° C. in a vacuum drying oven (Lexan®145, of General Electric) is charged with the stabilizers listed in Table 19 and is mixed for 2 minutes in a Henschel mixer. This mixture is then extruded in a Schwabenthan extruder at a maximum of 280° C. The polymer string is then granulated. Using an injection moulding machine, plates having a layer thickness of 2 mm are then moulded from the granulate so obtained at a maximum of 300° C. These plates are then aged in a circulating air oven at 135° C., the time in hours until the yellowness index (YI) reaches a value of 20 according to ASTM D 1925-70 being measured. The longer the time, the more effective the stabilizer. The results are compiled in Table 19. TABLE 19 Time in hours at Example Stabilizers 135° C. to YI = 20 17a^(i)) — 1560 17b^(i))  0.05% Irgafos ® 168^(a)) 2000 17c^(k)) 0.006% Compound (106) 2350 0.022% Irgafos ® 168^(a)) 0.012% Irganox ® 1076^(n)) 17d^(k)) 0.009% Compound (106) 2350 0.034% Irgafos ® 168^(a)) 0.017% Irganox ® 1076^(n))

[0521] For footnotes a), i), k) and n) see the end of Table 25.

EXAMPLE 18 Stabilisation of Polybutylene Terephthalate (PBT)

[0522] 1.0 kg of a polybutylene terephthalate powder which has been dried for 10 hours at 100° C. in a vacuum drying oven (Crastin®S600, of Ciba Specialty Chemicals Inc.) is charged with the stabilizers listed in Table 20 and is mixed for 2 minutes in a Henschel mixer. This mixture is then extruded in a twin-screw extruder (type Berstorff) at a maximum of 250° C. and is then granulated. In an injection moulding apparatus, the granulate so obtained is moulded at a maximum of 260° C. to little rods 4×6 mm thick and 50 mm long. These little rods are then aged in a circulating air oven at 160° C. After 360 hours the impact strength of the rods is measured in KJ/m². The higher the values, the better the stabilization. The results are compiled in Table 20. TABLE 20 Impact strength in the oven-ageing test at 160° C. Impact strength in KJ/m² Example Stabilizers after 0 h after 360 h 18a^(i)) — 130 26 18b^(i)) 0.05% Irganox ® 245^(o)) 132 111 18c^(i)) 0.10% Irganox ® 245^(o)) 135 114 18d^(i)) 0.05% Irganox ® 245^(o)) 134 110 0.05% Irgafos ® 168^(a)) 18e^(k)) 0.05% Irganox ® 245^(o)) 133 130 0.05% Irgafos ® 168^(a)) 0.02% compound (109)^(d))

[0523] For footnotes a), i), k) and o) see the end of Table 25.

EXAMPLE 19 Stabilization of Polycarbonate

[0524] 1.0 kg of a polycarbonate powder which has been dried for 8 hours at 120° C. in a vacuum drying oven (Lexan®145, of General Electric) is charged with the stabilizers listed in Table 21 and is mixed for 2 minutes in a Henschel mixer. This mixture is then extruded in a Schwabenthan extruder at a maximum of 280° C. The polymer string is then granulated. Using an injection moulding machine, plates having a layer thickness of 2 mm are then moulded from the granulate so obtained at a maximum of 300° C. These plates are then irradiated in a Weather-O-Meter (WOM CI 65) for 2500 hours at a black standard temperature of 63° C., at a dry/wet cycle of 102/18 minutes and at an intensity of 0.35 W/m² at 340 nm. The yellowness index (YI) of these plates is then determined according to ASTM D 1925-70. Low YI values denote little discoloration, high YI values high discoloration of the plates. The less discoloration, the more effective the stabilizer or the stabilizer mixture. The results are compiled in Table 21. TABLE 21 Yellowness index Example Stabilizers after 2500 h exposure to light 19a^(i)) — 30.2 19b^(i)) 0.30% Tinuvin ® 234^(p)) 17.8 19c^(i)) 0.30% Tinuvin ® 360^(q)) 16.6 19d^(i)) 0.30% Tinuvin ® 1577^(r)) 11.2 19e^(k)) 0.30% Tinuvin ® 234^(p)) 16.5 0.02% Compound (102) 19f^(k)) 0.30% Tinuvin ® 360^(q)) 15.0 0.02% Compound (102) 19g^(k)) 0.30% Tinuvin ® 1577^(r)) 9.5 0.02% Compound (102) 19h^(k)) 0.30% Tinuvin ® 234^(p)) 13.4 0.05% Irgafos ® 168^(a)) 0.02% Compound (102) 19i^(k)) 0.30% Tinuvin ® 360^(q)) 12.0 0.05% Irgafos ® 168^(a)) 0.02% Compound (102) 19j^(k)) 0.30% Tinuvin ® 1577^(r)) 9.2 0.05% Irgafos ® 168^(a)) 0.02% Compound (101)

[0525] For footnotes a), i), k), p), q) and r) see the end of Table 25.

EXAMPLE 20 Stabilization of Polycarbonate

[0526] 1.0 kg of a polycarbonate powder which has been dried for 8 hours at 120° C. in a vacuum drying oven (Lexan®145, of General Electric) is charged with the stabilizers listed in Table 22 and is then mixed for 2 minutes in a Henschel mixer. This mixture is then extruded in a Schwabenthan extruder at a maximum of 280° C. The polymer string is then granulated. The granulate so obtained is packed into 1 cm thick polystyrene boxes and the yellowness index (YI) is determined according to ASTM D 1925-70. Low YI values denote little discoloration, high YI values high discoloration of the samples. The less discoloration, the more effective the stabilizer or the stabilizer mixture. The results are compiled in Table 22. TABLE 22 Example Stabilizers Yellowness index 6a^(i)) — 10.3 6b^(i)) 0.05% GSY ® P101^(s)) 5.1 6c^(k)) 0.04% GSY ® P101^(s)) 1.0 0.02% Compound (104)

[0527] For footnotes i), k) and s) see the end of Table 25.

EXAMPLE 21 Stabilization of Polyesters

[0528] 2.5 kg of a polyester which has been dried for 12 hours at 120° C. in a vacuum drying oven (Polyclear® T86, of Hoechst) is charged with the stabilizers listed in Table 23 and is mixed for 2 hours in a Henschel mixer. This mixture is then extruded in a Schwabenthan extruder at a maximum of 275° C. The polymer string is then granulated. The granulate so obtained is dried for another 12 hours in a vacuum drying oven. In a double determination, 500 mg of the granulate is heated over 10 minutes to 290° C. and is stored for 1 hour under pure oxygen in a rancimate at 290° C. The resulting gaseous separation products are continuously led into an aqueous collecting solution and the conductivity (μS) of this solution is continuously measured. Low conductivity values signify that few separation products are formed, high conductivity values signify that very many separation products are formed. The lower the conductivity values, the more effiective the stabilizer. The results are compiled in Table 23. TABLE 23 Example Stabilizers Conductivity (μS) 21a^(i)) — 47 21b^(k)) 0.20% Compound (107) 34

[0529] For footnotes i) and k) see the end of Table 25.

EXAMPLE 22 Stabilization of Light-colored SBR-vulcanisate (Ozone Atmosphere for 48 Hours)

[0530] 100 parts by weight of Cariflex®S-1502 (styrene/butadiene rubber, Shell) are processed at 60° C., in a mixing mill, with 30.0 parts by weight of Kronos®CL 220 [titanium dioxide (pigment), Kronos Titan GmbH], 30.0 parts by weight of Aktisil®MM [kaolin (filler), Hoffmann Mineral, Neuburg/Donau], 5.0 parts by weight of Naftolen®N 401 [plasticizer, Metallgesellschaft], 10.0 parts by weight of zinc oxide [vulcanization activator], 2.0 parts by weight of stearic acid [vulcanization activator], 2.0 parts by weight of sulfur [vulcanizing agent], 1.0 part by weight of Vulkacit®MOZ [vulcanisation accelerator, Bayer], 0.25 part by weight of Vulkacit®Thiuram [vulcanization accelerator, Bayer] and 1.0 part by weight of the stabilizer to be tested according to Table 24, to form a homogeneous mixture, the vulcanization system (sulfur, Vulkacit®MOZ and Vulkacit®Thiuram) not being added until the end of the mixing process. The mixture is vulcanized in electrical vulcanization presses at 150° C. until T95 is reached in the rheometer curves to form elastomer plates 2 mm thick, 21 cm long and 8.0 cm wide.

[0531] Some of the elastomer plates so obtained are tested for the action of ozone according to the ASTM standard D 3395-86 while subject to dynamic elongation. In this test, the plates are first stored for 30 days in a standard atmosphere [23/50 SN-ISO 291]. Test specimens measuring 20 cm by 1 cm are then punched out and exposed to an ozone atmosphere for 48 hours (ozone content: 50 pphm; temperature: 40° C.; humidity: 50% rel.; elongation: 0 to 25%; elongation rate: 0.5 Hz; number of load cycles: approximately 173 000). The test plates are then assessed for crack formation according to ASTM D 3395-86. Grade 0 denotes no cracks; grade 1 denotes narrow flat cracks; grade 2 denotes moderately broad, moderately deep cracks, clearly visible; grade 3 denotes broad and deep cracks. The lower the grade number, the better the stabilization of the elastomer plates. The results are compiled in Table 24.

[0532] The remaining elastomer plates are stored for 3 weeks at room temperature in a standard laboratory atmosphere in diffuse daylight. The ΔL-color of those plates is then determined according to DIN 6167, which corresponds to a scale of from 0 to 100. No discoloration is indicated by a value of 100. The results are compiled in Table 24. TABLE 24 Crack formation ΔL-color according to according to Examples Stabilizer ASTM D 3395-86 DIN 6167 Example 22a^(i)) — grade 1-2 94 Example 22b^(i)) 1.0 phr^(u)) Vulka- grade 0 70 nox ® 4010^(t)) Example 22c^(k)) 1.0 phr^(u)) Compound grade 0-1 96 (108)

[0533] For footnotes i), k), t and u) see the end of Table 25.

EXAMPLE 23 Stabilisation of Light-colored SBR-vulcanisate (Ozone Atmosphere for 96 Hours)

[0534] 100 parts by weight of Cariflex®S-1502 (styrene/butadiene rubber, Shell) are processed at 60° C., in a mixing mill, with 30.0 parts by weight of Kronos®CL 220 [titanium dioxide (pigment), Kronos Titan GmbH], 30.0 parts by weight of Aktisil®MM [kaolin (filler), Hoffmann Mineral, Neuburg/Donau], 5.0 parts by weight of Naftolen®N 401 [plasticiser, Metallgesellschaft], 10.0 parts by weight of zinc oxide [vulcanization activator], 2.0 parts by weight of stearic acid [vulcanization activator], 2.0 parts by weight of sulfur [vulcanizing agent], 1.0 part by weight of Vulkacit®MOZ [vulcanization accelerator, Bayer], 0.25 part by weight of Vulkacit®Thiuram [vulcanization accelerator, Bayer] and 1.0 part by weight of the stabilizer to be tested according to Table 25, to form a homogeneous mixture, the vulcanization system (sulfur, Vulkacit®MOZ and Vulkacit®Thiuram) not being added until the end of the mixing process. The mixture is vulcanized in electrical vulcanization presses at 150° C. until T95 is reached in the rheometer curves to form elastomer plates 2 mm thick, 21 cm long and 8.0 cm wide.

[0535] Some of the elastomer plates so obtained are tested for the action of ozone according to the ASTM standard D 3395-86 while subject to dynamic elongation. In this test the plates are first stored for 30 days in a standard atmosphere [23/50 SN-ISO 291]. Test specimens measuring 20 cm by 1 cm are then punched out and exposed to an ozone atmosphere for 96 hours (ozone content: 50 pphm; temperature: 40° C.; humidity: 50% rel.; elongation: 0 to 25%; elongation rate: 0.5 Hz; number of load cycles: approximately 173 000). The test plates are then assessed for crack formation according to ASTM D 3395-86. Grade 0 denotes no cracks; grade 1 denotes narrow flat cracks; grade 2 denotes moderately broad, moderately deep cracks, clearly visible; grade 3 denotes broad and deep cracks. The lower the grade number, the better the stabilization of the elastomer plates. The results are compiled in Table 25.

[0536] The remaining elastomer plates are stored for 3 weeks at room temperature in a standard laboratory atmosphere in diffuse daylight. The ΔL-color of those plates is then determined according to DIN 6167, which corresponds to a scale of from 0 to 100. No discoloration is indicated by a value of 100. The results are compiled in Table 25. TABLE 25 Crack formation ΔL-color according to according to Examples Stabilizer ASTM D 3395-86 DIN 6167 Example 23a^(i)) — grade 2 97 Example 23b^(i)) 2.0 phr^(u)) Vulkanox ®4010^(t)) grade 0 56 Example 23c^(k)) 2.0 phr^(u)) compound 101 grade 1 95 Example 23d^(k)) 2.0 phr^(u)) compound 106 grade 1 95 Example 23e^(k)) 2.0 phr^(u)) compound 108 grade 1 95 ^(a))Irgafos ®168 (Ciba Specialty Chemicals Inc.) is tris(2,4-di-tert-butylphenyl)phosphite. ^(b))Sandostab ®P-EPQ (Clariant) is tetrakis(2,4-di-tert-butylphenyl)-4,4′-biphenylene diphosphonite. ^(c))Irganox ®5057 (Ciba Specialty Chemicals Inc.) is a secondary amine antioxidant and is a technical mixture, obtained by reaction of diphenylamine with diisobutylene, comprising a′) 3% of diphenylamine; b′) 14% of 4-tert-butyldiphenylamine; c′) 30% of compounds of the group i) 4-tert-octyldiphenylamine, ii) 4,4′-di-tert-butyldiphenylamine, iii) 2,4,4′-tris-tert-butyldiphenylamine; d′) 29% of the compounds of the group i) 4-tert-butyl-4′-tert-octyldiphenylamine, ii) o,o′-,m,m′-or p,p′-di-tert-octyldiphenylamine, iii) 2,4-di-tert-butyl-4′-tert-octyldiphenylamine; e′) 24% of the compounds of the group i) 4,4′-di-tert-octyldiphenylamine and ii) 2,4-di-tert-octyl-4′-tert-butyldiphenylamine. ^(d))Irganox ® 1135 (Ciba Specialty Chemicals Inc.) is a phenolic antioxidant of the formula A-1.

^(e))Tinuvine622 (Ciba Specialty Chemicals Inc.) is a compound of the formula H1 in which the average molecular weight is about 3000.

^(f))Chimassor ®9944 (Ciba Specialty Chemicals Inc.) denotes linear or cyclic condensation products prepared from N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylendiamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine and is a compound of the formula H2 in which the average molecular weight is about 2500.

^(g))Chimassorb ®119 (Ciba Specialty Chemicals Inc.) denotes condensation products prepared from 2-chloro-4,6-di(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)-1,3,5-triazine and 1,2-bis(3-aminopropylamino)ethane and is a compound of the formula H3

^(h))Irgafos ®38 (Ciba Specialty Chemicals Inc.) is a compound of the formula P-1.

^(i))Comparison Example. ^(k))Example of this invention. ^(l))Irganox ®1010 (Ciba Specialty Chemicals Inc.) denotes the pentaerythritol ester of 3-(3,5- di-tert-butyl-4-hydroxyphenyl)propionic acid. ^(m))HALS mixture is a 1:1 mixture of Tinuvin ®622 [Ciba Specialty Chemicals Inc.; see foot- note e)] and Chimassorbl ®119 (Ciba Specialty Chemicals Inc.; see footnote g)]. ^(n))Irganox ®1076 (Ciba Specialty Chemicals Inc.) denotes a compound of formula A-2.

^(o))Irganox ®245 (Ciba Specialty Chemicals Inc.) denotes a compound of formula A-3.

^(p))Tinuvin ®234 (Ciba Specialty Chemicals Inc.) denotes a compound of formula UV-1.

^(q))Tinuvin ®360 (Ciba Specialty Chemicals Inc.) denotes a compound of formula UV-2.

^(r))Tinuvin ®1577 (Ciba Specialty Chemicals Inc.) denotes a compound of formula UV-3.

^(s))GSY ®P101 (Yoshitomi) denotes a compound of formula P-2.

^(t))Vulkanox ®4010 (Bayer) denotes 4-isopropytamino-diphenylamine of formula A.

^(u))phr denotes “parts per hundred of rubber.” 

What is claimed is:
 1. A compound of the formula I

wherein, when n is 1, R₁ is a radical of the formula II, III or IV

and when n is 2, R₁ is

R₂, R₃, R₄ and R₅ are each independently of one another hydrogen, chloro, hydroxyl, C₁-C₂₅-alkyl, C₇-C₉phenylalkyl, unsubstituted or C₁-C₄alkyl-substituted phenyl; unsubstituted or C₁-C₄alkyl-substituted C₅-C₈cycloalkyl; C₁-C₁₈alkoxy, C₁-C₁₈alkylthio, C₁-C₄alkylamino, di-(C₁-C₄alkyl)amino, C₁-C₂₅alkanoyloxy, C₁-C₂₅alkanoylamino, C₃-C₂₅alkenoyloxy, C₃-C₂₅alkanoyloxy which is interrupted by oxygen, sulfur or

C₆-C₉cycloalkylcarbonyloxy, benzoyloxy or C₁-C₁₂alkyl-substituted benzoyloxy; or each pair of substituents R₂ and R₃ or R₃ and R₄ or R₄ and R₅ together with the linking carbon atoms, forms a benzene ring; or R₄ is additionally —(CH₂)_(p)—COR₁₉ or —(CH₂)_(q)OH, or when R₃, R₅ and R₆ are hydrogen, R₄ is additionally a radical of the formula V

wherein R₁ is as defined above for n=1, R₆ is hydrogen or a radical of the formula VI

in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ and R₁₅ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₁₂alkyl; —CN,

—SOR₂₆, —SO₂R₂₆ or SO₃R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ or R₁₅ is not hydrogen, R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene which are substituted by fluoro, fluoro-substituted C₁-C₁₂alkyl, —CN,

—SOR₂₆, —SO₂R₂₆ or SO₃R₂₆, R₁₈ is hydrogen or C₁-C₈alkyl, R₁₉ is hydroxyl, $\left\lbrack {{—O}^{-}\frac{1}{r}M^{r +}} \right\rbrack,$

C₁-C₁₉alkoxy or

R₂₀ and R₂₁ are each independently of one another hydrogen, CF₃, C₁-C₁₂alkyl or phenyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a C₅-C₈cycloalkylidene ring which is unsubstituted or substituted by 1 to 3 C₁-C₄alkyl groups; R₂₂ is hydrogen, hydroxyl, $\left\lbrack {{—O}^{-}\frac{1}{r}M^{r +}} \right\rbrack,$

C₁-C₂₅alkyl, C₇-C₉phenylalkyl, unsubstituted or C₁-C₄alkyl-substituted phenyl; unsubstituted or C₁-C₄alkyl-substituted C₅-C₈cycloalkyl; or C₃-C₂₅alkyl which is interrupted by oxygen, sulfur or

R₂₃ is C₁-C₂₅alkyl, C₇-C₉phenylalkyl, unsubstituted or C₁-C₄alkyl-substituted phenyl; unsubstituted or C₁-C₄alkyl-substituted C₅-C8cycloalkyl; or C₃-C₂₅alkyl which is interrupted by oxygen, sulfur or

R₂₄ and R₂₅ are each independently of one another hydrogen, C₁-C₂₅alkyl, hydroxyl-substituted C₂-C₂₄alkyl; C₃-C₂₅alkyl which is interrupted by oxygen, sulfur or

C₇-C₉-phenylalkyl which is unsubstituted or is substituted on the phenyl ring by C₁-C₄alkyl; or C₃-C₂₄alkenyl; or R₂₄ and R₂₅, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring which is unsubstituted or is substituted by C₁-C₄alkyl or is interrupted by oxygen, sulfur or

R₂₆ is hydrogen or C₁-C₂₅alkyl, R₂₇ and R₂₈ are each independently of one another hydrogen, C₁-C₂₅alkyl, hydroxyl-substituted C₂-C₂₄alkyl; C₃-C₂₅alkyl which is interrupted by oxygen, sulfur or

C₇-C₉-phenylalkyl which is unsubstituted or is substituted on the phenyl ring by C₁-C₄alkyl; or C₃-C₂₄alkenyl; or R₂₇ and R₂₈, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring which is unsubstituted or is substituted by C₁-C₄alkyl or is interrupted by oxygen, sulfur or

R₂₉ and R₃₀ are each independently of one another hydrogen, C₁-C₁₈alkyl or C₇-C₉phenylalkyl, or R₂₉ and R₃₀ together with the nitrogen atom to which they are attached form a 5-, 6- or 7-membered heterocyclic ring which is unsubstituted or is substituted by C₁-C₄alkyl or is interrupted by oxygen, sulfur or

X₁ is a direct bond, C₁-C₁₈alkylene, C₂-C₁₈alkylene which is interrupted by oxygen, sulfur or

C₂-C₁₆alkenylene, C₂-C₂₀alkylidene, C₇-C₂₀phenylalkylidene, C₅-C₈cycloalkylene, C₇-C₈bicycloalkylene, unsubstituted or C₁-C₄alkyl-substituted phenylene,

—O—X₃—O—, X₂ is C₂-C₁₈alkylene, C₄-C₁₈alkylene which is interrupted by oxygen, sulfur or

C₂-C₁₈alkenylene, C₅-C₈cycloalkylene, C₇-C₈bicycloalkylene, unsubstituted or C₁-C₄alkyl-substituted phenylene,

X₃ is C₂-C₁₈alkylene, C₄-C₁₈alkylene which is interrupted by oxygen, sulfur or

C₂-C₁₈alkenylene, C₅-C₈cycloalkylene, C₇-C₈bicycloalkylene, unsubstituted or C₁-C₄alkyl-substituted phenylene,

M is a metal cation of valency r, n is 1 or 2, p is 0, 1 or 2, q is 1, 2, 3, 4, 5 or 6, and r is 1, 2 or
 3. 2. A compound according to claim 1, wherein, when n is 1, R₁ is a radical of the formula II, III or IV

and when n is 2, R₁ is

R₂, R₃, R₄ and R₅ are each independently of one another hydrogen, chloro, hydroxyl, C₁-C₁₈-alkyl, C₇-C₉phenylalkyl, phenyl, C₅-C₈cycloalkyl, C₁-C₁₈alkoxy, C₁-C₁₈alkylthio, C₁-C₁₈alkanoyloxy, C₁-C₁₈alkanoylamino, C₃-C₁₈alkenoyloxy, C₃-C₁₈alkanoyloxy which is interrupted by oxygen or sulfur; C₆-C₉cycloalkylcarbonyloxy, benzoyloxy or C₁-C₄alkyl-substituted benzoyloxy; or each pair of substituents R₂ and R₃ or R₃ and R₄ or R₄ and R₅ together with the linking carbon atoms, forms a benzene ring; or R₄ is additionally —(CH₂)_(p)—COR₁₉ or —(CH₂)_(q)OH, or when R₃, R₅ and R₆ are hydrogen, R₄ is additionally a radical of the formula V

wherein R₁ is as defined above for n=1, R₆ is hydrogen or a radical of the formula VI

in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ and R₁₅ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₈alkyl; —CN,

—SOR₂₆, —SO₂R₂₆ or SO₃R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ or R₁₅ is not hydrogen, R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene which are substituted by fluoro, trifluoromethyl, —CN,

, —SOR₂₆, —SO₂R₂₆ or SO₃R₂₆, R₁₈ is hydrogen or C₁-C₄alkyl, R₁₉ is hydroxyl, $\left\lbrack {{—O}^{-}\frac{1}{r}M^{r +}} \right\rbrack,$

, C₁-C₁₈alkoxy or

, R₂₀ and R₂₁ are each independently of one another hydrogen, CF₃, C₁-C₈alkyl or phenyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a C₅-C₈cycloalkylidene ring; R₂₂ is hydrogen, hydroxyl, $\left\lbrack {{—O}^{-}\frac{1}{r}M^{r +}} \right\rbrack,$

, C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, C₅-C₈-cycloalkyl; or C₃-C₂₅alkyl which is interrupted by oxygen or sulfur, R₂₃ is C₁-C₂₂alkyl, C₇-C₉phenylalkyl, phenyl, C₅-C₈cycloalkyl or C₃-C₂₅alkyl which is interrupted by oxygen or sulfur, R₂₄ and R₂₅ are each independently of one another hydrogen, C₁-C₁₈alkyl, hydroxyl-substituted C₂-C₁₈alkyl; C₃-C₁₈alkyl which is interrupted by oxygen, sulfur or

; C₇-C₉-phenylalkyl, or C₃-C₁₈alkenyl; or R₂₄ and R₂₅, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring, R₂₆ is hydrogen or C₁-C₁₈alkyl, R₂₇ and R₂₈ are each independently of one another hydrogen, C₁-C₁₈alkyl, hydroxyl-substituted C₂-C₁₈alkyl; C₃-C₁₈alkyl which is interrupted by oxygen, sulfur or

; C₇-C₉-phenylalkyl, or C₃-C₁₈alkenyl; or R₂₇ and R₂₈, together with the nitrogen atom to which they are attached, form a 5-, 6- or 7-membered heterocyclic ring, R₂₉ and R₃₀ are each independently of one another hydrogen, C₁-C₁₈alkyl or C₇-C₉phenylalkyl, or R₂₉ and R₃₀ together with the nitrogen atom to which they are attached form a 5-, 6- or 7-membered heterocyclic ring, X₁ is a direct bond, C₁-C₁₂alkylene, C₂-C₁₈alkylene which is interrupted by oxygen or sulfur; C₂-C₁₂alkenylene, C₂-C₁₂alkylidene, C₁-C₁₂phenylalkylidene, C₅-C₈cycloalkylene, phenylene,

—O—X₃—O—, X₂ is C₂-C₁₂alkylene, C₄-C₁₂alkylene which is interrupted by oxygen, sulfur or

; C₂-C₁₂alkenylene, C₅-C₈cycloalkylene, phenylene,

X₃ is C₂-C₁₈alkylene, C₄-C₁₂alkylene which is interrupted by oxygen, sulfur or

; C₂-C₁₂alkenylene, C₅-C₈cycloalkylene, phenylene,

M is a metal cation of valency r, n is 1 or 2, p is 0, 1 or 2, q is 1, 2, 3, 4, 5 or 6, and r is 1, 2 or
 3. 3. A compound according to claim 1, wherein, when n is 1, R₁ is a radical of the formula II, III or IV, and when n is 2, R₁ is

, R₂, R₃, R₄ and R₅ are each independently of one another hydrogen, C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, cyclohexyl, C₁-C₁₂alkoxy, C₁-C₁₂alkylthio, C₁-C₁₂alkanoyloxy, C₃-C₁₂alkenoyloxy, C₃-C₁₂alkanoyloxy which is interrupted by oxygen; cyclohexylcarbonyloxy, benzoyloxy or each pair of substituents R₂ and R₃ or R₃ and R₄ or R₄ and R₅ together with the linking carbon atoms, forms a benzene ring; or R₄ is additionally —(CH₂)_(p)—COR₁₉ or —(CH₂)_(q)OH, or when R₃, R₅ and R₆ are hydrogen, R₄ is additionally a radical of the formula V, wherein R₁ is as defined above for n=1, R₆ is hydrogen or a radical of the formula VI in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1, R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ and R,₁₅ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₄alkyl; —CN,

—SOR₂₆, —SO₂R₂₆ or SO₃R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀, R₁₁, R₁₂, R₁₃, R₁₄ or R₁₅ is not hydrogen, R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene, R₁₉ is hydroxyl, C₁-C₁₈alkoxy or

R₂₀ and R₂₁ are each independently of one another hydrogen, CF₃ or C₁-C₄alkyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a cyclohexylidene ring; R₂₂ is hydroxyl, C₁-C₁₂alkyl, phenyl, cyclohexyl or C₃-C₁₂alkyl which is interrupted by oxygen, R₂₃ is C₁-C₂₂alkyl, benzyl, phenyl, cyclohexyl or C₃-C₁₂alkyl which is interrupted by oxygen, R₂₄ and R₂₅ are each independently of one another hydrogen, C₁-C₁₂alkyl, hydroxyl-substituted C₂-C₁₂alkyl; C₃-C₁₂alkyl which is interrupted by oxygen; benzyl or C₃-C₁₂alkenyl; or R₂₄ and R₂₅, together with the nitrogen atom to which they are attached, form 6-membered heterocyclic ring, R₂₆ is C₁-C₁₂alkyl, R₂₇ and R₂₈ are each independently of one another hydrogen, C₁-C₁₂alkyl, hydroxyl-substituted C₂-C₁₂alkyl; C₃-C₁₈alkyl which is interrupted by oxygen; benzyl or C₃-C₁₂alkenyl; or R₂₇ and R₂₈, together with the nitrogen atom to which they are attached, form 6-membered heterocyclic ring, R₂₉ and R₃₀ are each independently of one another hydrogen, C₁-C₁₂alkyl or benzyl, or R₂₉ and R₃₀ together with the nitrogen atom to which they are attached form a 6-membered heterocyclic ring, X₁ is a direct bond, C₁-C₈alkylene, C₂-C₁₈alkylene which is interrupted by oxygen; phenylene,

or —O—X₃O—, X₂ is C₂-C₈alkylene, C₄-C₁₂alkylene which is interrupted by oxygen; cyclohexylene, phenylene,

X₃ is C₂-C₁₈alkylene, C₄-C₁₂alkylene which is interrupted by oxygen; C2-C₁₂alkenylene, cyclohexylene, phenylene,

, n is 1 or 2, p is 1 or 2, and q is 2 or
 3. 4. A compound according to claim 1, wherein, when n is 1, R₁ is a radical of the formula II, and when n is 2, R₁ is

, R₂ is hydrogen, C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, cyclohexyl, C₁-C₈alkanoyloxy or benzoyloxy, R₃ is hydrogen or C₁-C₄alkyl, R₄ is hydrogen, C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, cyclohexyl, C₁-C₈alkanoyloxy, —(CH₂)_(p)—COR₁₉ or —(CH₂)_(q)OH, or when R₃, R₅ and R₆ are hydrogen, R₄ is additionally a radical of the formula V, wherein R₁ is as defined above for n=1, R₅ is hydrogen or C₁-C₄alkyl, R₆ is hydrogen or a radical of the formula VI in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1, R₇, R₈, R₉, R₁₀ and R₁₁ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₄alkyl; —CN,

, —SOR₂₆, or —SO₂R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀ or R₁₁ is not hydrogen, R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene, R₁₉ is C₁-C₈alkoxy, R₂₀ and R₂₁ are each independently of one another hydrogen, CF₃ or C₁-C₄alkyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a cyclohexylidene ring; R₂₃ is C₁-C₂₂alkyl, benzyl, phenyl, cyclohexyl or C₃-C₁₂alkyl which is interrupted by oxygen, R₂₄ and R₂₅ are each independently of one another hydrogen, C₁-C₄alkyl, hydroxyl-substituted C₂-C₄alkyl; C₃-C₁₂alkyl which is interrupted by oxygen; benzyl or C₃-C₁₂alkenyl, R₂₆ is C₁-C₈alkyl, R₂₉ and R₃₀ are each independently of one another hydrogen, C₁-C₈alkyl or benzyl, X₁ is a direct bond, C₁-C₈alkylene,

or —O—X₃—O—, X₂ is C₂-C₈alkylene or C₄-C₁₂alkylene which is interrupted by oxygen, X₃ is C₂-C₁₈alkylene or C₄-C₁₂alkylene which is interrupted by oxygen, n is 1 or 2, p is 1 or 2, and q is 2 or
 3. 5. A compound according to claim 1, wherein, when n is 1, R₁ is a radical of the formula II, and when n is 2, R₁ is

R₂ is C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl or cyclohexyl, R₃ is hydrogen or methyl, R₄ is hydrogen, C₁-C₁₈alkyl, C₇-C₉phenylalkyl, phenyl, cyclohexyl or a radical of the formula V, wherein R₁ is as defined above for n=1, R₅ is hydrogen or methyl, R₆ is hydrogen or a radical of the formula VI in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1, R₇, R₈, R₉, R₁₀ and R₁₁ are each independently of one another hydrogen, fluoro, fluoro-substituted C₁-C₄alkyl; —CN,

, —SOR₂₆, or —SO₂R₂₆; with the proviso that at least one of R₇, R₈, R₉, R₁₀ or R₁₁ is not hydrogen, R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene, R₂₀ and R₂₁ are each independently of one another hydrogen or C₁-C₄alkyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a cyclohexylidene ring; R₂₃ is C₁-C₂₂alkyl, benzyl, phenyl, cyclohexyl or C₃-C₁₂alkyl which is interrupted by oxygen, R₂₆ is C₁-C₈alkyl, X₁ is a direct bond, C₁-C₈alkylene or —O—X₃—O—, X₃ is C₂-C₁₈alkylene or C₄-C₁₂alkylene which is interrupted by oxygen, and n is 1 or
 2. 6. A compound according to claim 1, wherein, when n is 1, R₁ is a radical of the formula II, and when n is 2, R₁ is

R₂ is C₁-C₈alkyl or cyclohexyl, R₃ is hydrogen, R₄ is hydrogen, C₁-C₈alkyl, cyclohexyl or a radical of the formula V, wherein R₁ is as defined above for n=1, R₅ is hydrogen, R₆ is hydrogen or a radical of the formula VI in which R₄ is not a radical of the formula V and R₁ is as defined above for n=1, R₇, R₈, R₉, R₁₀ and R₁₁ are each independently of one another hydrogen, fluoro, trifluoromethyl; —CN or

, with the proviso that at least one of R₇, R₈, R₉, R₁₀ or R₁₁ is not hydrogen, R₁₆ and R₁₇ are each independently of one another phenylene or naphthylene, R₂₀ and R₂₁ are each independently of one another hydrogen or C₁-C₄alkyl, or R₂₀ and R₂₁ together with the linking carbon atom, form a cyclohexylidene ring; R₂₃ is C₁-C₂₂alkyl, benzyl or cyclohexyl, X₁ is C₁-C₈alkylene or —O—X₃—O—, X₃ is C₂-C₁₄alkylene, and n is 1 or
 2. 7. A compound according to claim 1, wherein when n is 1, R₁ is a radical of the formula II, and when n is 2, R₁ is

R₂ is C₁-C₄alkyl, R₃ is hydrogen, R₄ is C₁-C₄alkyl, R₅ is hydrogen, R₆ is hydrogen or a radical of the formula VI wherein R₁ is as defined above for n=1, R₇ is hydrogen or trifluoromethyl, R₈ is hydrogen, trifluoromethyl or —CN, R₉ is hydrogen or trifluoromethyl, R₁₀ is hydrogen, trifluoromethyl or —CN, R₁₁ is hydrogen, fluoro, trifluoromethyl, —CN or

, with the proviso that at least one of R₇, R₈, R₉, R₁₀ or R₁₁ is not hydrogen, R₁₆ and R₁₇ are phenylene or naphthylene, R₂₃ is C₁-C₂₂alkyl, X₁ is —O—X₃—O—, X₃ is C₄-C₁₂alkylene, and n is 1 or
 2. 8. A composition comprising a) an organic material which is susceptible to oxidative, thermal or light-induced degradation, and b) at least one compound of the formula I according to claim
 1. 9. A composition according to claim 8, wherein component (a) is selected from the group consisting of a lubricant, a fuel, a hydraulic fluid, a metal-working fluid and a natural, semisynthetic or synthetic polymer.
 10. A composition according to claim 8, comprising as component (a) an engine oil, a turbine oil, a gear oil, a diesel fuel or a lubricating grease.
 11. A composition according to claim 8, comprising as component (a) a synthetic polymer.
 12. A composition according to claim 8, wherein component (b) is present in an amount of from 0.0005 to 10%, based on the weight of component (a).
 13. A composition according to claim 8, comprising in addition, besides components (a) and (b), further additives.
 14. A composition according to claim 13, comprising as further additives phenolic antioxidants, light-stabilizers and/or processing stabilizers.
 15. A process for stabilizing an organic material against oxidative, thermal or light-induced degradation, which comprises incorporating therein or applying thereto at least one compound of the formula I according to claim
 1. 16. Use of a compound of the formula I according to claim 1 as stabilizer for an organic material against oxidative, thermal or light-induced degradation.
 17. A color photographic material comprising a compound of formula I according to claim
 1. 18. A color photographic material according to claim 17, comprising the compound of the formula I in a non-photosensitive interlayer.
 19. A color photographic material according to claim 17, comprising the compound of the formula I in an amount from 10 to 1000 mg/m².
 20. Use of a compound of formula I according to claim 1 as scavenger for the oxidized developer in color photographic material.
 21. A process for preventing migration of the oxidized developer in a color photographic material from one color sensitive layer to another by incorporating a compound of the formula I according to claim 1 into said material. 